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How Far From Earth Can Humans Travel Into Space?

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Space travel as far we currently understand it is complicated.  Fer Gregory/Shutterstock.com

As of 2021, Americans James Lovell, Fred Haise, John Swigert are the three people who have traveled furthest from Earth, during the Apollo 13 mission. When they flew behind the Moon, they were 400,171 kilometers (248,655 miles) from the surface of the Earth. Light takes 1.335 seconds to cover that distance.

Many of us have certainly fantasized about going into the stars, or at least exploring the solar system. The feasibility of doing that safely is still slightly out of reach, but we are certainly striding towards further and further forays away from the comfort and safety of our own planet.

Could we reach other planets? Very likely. How about other stars? Maybe one day. What about the end of the universe? There is actually a way that doesn’t require any science fiction solutions (or at least nothing beyond the physics we know.)

Let’s look at the technologies we need to go further deep into space.

The Moon, Mars, and Beyond

If our goal is to explore the solar system, we have a lot of the technology already. There are powerful rockets already in use, and crewed vehicles are being designed to carry humans back to the Moon and beyond – but there are many concerns.

The further we are away from Earth, the higher dose of cosmic radiation we receive. Our planet’s strong magnetic field shields from a good chunk of that. What’s protecting you when you’re going into deep space? Researchers have actually tested a solution. Fungi discovered in Chernobyl survives on radiation, and this could one day be used as a living shielding system on spacecraft and human habitats.

Journeys also would take many months – if not years – and there is a lot of talks of one-way trips. In general, everywhere else in the solar system is an extremely dangerous environment that can easily kill us. While we might reach it, this doesn’t mean we can thrive there. And remember that most medical interventions in space might be extremely difficult to perform.

There’s also the possibility that alien life exists somewhere nearby, so we need to discuss how our presence there might endanger the potential organisms living beyond Earth.

Ad Astra – To The Stars

If you think that all the challenges of “local” space travel can be solved (let’s believe they can for now), maybe you want to turn your attention towards the stars. Could humanity travel to another star system?

Humanity, maybe. A single human, not really. Let’s take Proxima Centauri, the closest star to the Sun. At the speed of light, it takes just over four years to get there. If we were to achieve the speed of the fastest spacecraft ever ( NASA's Parker Solar Probe in its closest approach to the Sun ) it would take almost 8,400 years to get there. And that’s without slowing down to stop it.

There are proposals to send robotic explorations there. Miniature crafts might get there in just a few decades, and larger nuclear-powered ones could do the journey in a few hundred years. Those are very exciting, but they are not suitable for humans. And even if they were, that’s still beyond the human lifespan.

A solution to this might be a generational ship. The first generation would leave our planet and their descendants would reach the star. Obviously, we should wonder why anyone would start this journey. But It’s equally important to discuss the ethical and psychological state that the in-between generations, these interstellar middle children, might be in. Would they be interested in keep going towards something they would never see?

Getting Close To The Speed Of Light

Can we make it faster? And could we reach nearby galaxies and beyond too? Well, at least in principle yes. What you would need is a relativistic rocket . This would allow a handful of humans to travel incredible distances, and it doesn’t require anything beyond our current understanding of physics.

You need a rocket that is accelerated by about 9.81 meters per second squared. That’s the average Earth-normal pull, so people in the spacecraft would feel like they are simply standing on the surface of our planet. Such an acceleration would quickly bring the spacecraft to relativistic speed and there a very useful phenomenon takes place: time dilation.

Getting close to the speed of light, the passage of time on the spacecraft will slow down. This quirk of physics was popularized in the twin paradox, and in this relativistic rocket, you are the twin that flies away and doesn’t age.

The clock outside would still be ticking. So, you could reach Proxima Centauri in 4.3 years, but on-board it would feel like 3.6 years. If you instead wanted to go Vega (27 light-years away), on board, it would feel like 6.6. The further you go the closer you’d be to the speed of light, and the slower time will pass.

Journey to the edge of the universe

So you could get to the center of the Milky Way in 20 years or to the Andromeda Galaxy – located over two million light-years away – in a merely 28. Obviously, two million years would have passed on Earth.

But there is a limit to how far we could go? Yes. The universe is expanding and this expansion is accelerated. The space between galaxies (unless they are very close) gets wider and wider with every passing second. And the further two things are in the universe the faster they appear to recede from each other.

There are galaxies that we see in the sky that we can no longer reach because the only way to do so would be to move faster than the speed of light to make up for the accelerated expansion of the universe. This border is called the cosmological horizon, and its exact size depends on the correct cosmological formula to describe the universe… which is currently a work in progress .

Still, it could be possible to reach this boundary in a few decades. An empty, cold, and unmarked border in the universe. So why don’t we have such a rocket? Well, fuel is the reason. To sustain such a constant acceleration requires a huge amount of fuel. Even imagining an extremely efficient reaction (that we don’t have), you ought to carry a lot of fuel with you. Like, a planet-size worth of fuel.

The moral of the story is that space travel as far we currently understand it is complicated. We have so many challenges to deal with, whether they are technical, physical, physiological, psychological, and ethical. How we approach them could make all the difference.

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Space: how far have we gone – and where are we going?

Billionaire entrepreneurs are trying to create rockets fit for human travel, while government agencies spend billions furthering their explorations. But we are still a long way off from making our way to the red planet

Who has travelled to space?

Space flight is now a venerable industry. Humanity’s first space explorer, Soviet cosmonaut Yuri Gagarin, orbited around the globe on 12 April 1961, more than half a century ago, when Britain remained a colonial power and people were still using halfpennies to buy their fish and chips.

Since then, more than 550 people have blasted themselves into the deep black abyss, although not all agree on how far up you need to go until you hit space, so there is no internationally accepted figure. Only a 10th of those have been women, in big part due to sexist policies by Nasa and Russia’s Roscosmos space agency.

Where have we been in space?

The Soviet Union pulled ahead with the first space walks, but US president John F Kennedy’s announcement that America would put a man on the moon by the end of the 1960s focused the space race squarely on that goal. Apollo 11 touched down on our dusty grey neighbour on 20 July 1969.

A total of 12 men walked on the moon over the next few years, all Americans, but no one has been back there since 1972. In fact, no one has left the outskirts of the Earth since then.

We imagine astronauts floating in free space or bouncing in moon craters, yet the majority of those lucky enough have instead spun around in low Earth’s orbit – between 99 and a few hundred miles high. That’s where the vast array of communications and navigation satellites live, speeding at thousands of miles an hour to avoid plummeting back to earth.

What do we do there?

Even though we did not go back to deep space, humans have begun to live and work outside the Earth’s atmosphere, often conducting experiments on themselves to determine the effects of weightlessness, or microgravity, on the human body.

By 1986, the Soviet Union had launched the Mir space station. When it eventually fell to Earth (thankfully unoccupied) and burned up, our current space outpost, the International Space Station (ISS), was launched. Since 2000, humans have been living in space constantly. There are three up there at the moment, speeding around the globe once every 90 minutes.

What happens to the body in space?

A lot, and until we properly understand how weightlessness affects humans, we won’t be able to send this era’s pioneers further afield to places such as Mars or wandering asteroids. Scott Kelly, a US former fighter pilot and long-time Nasa astronaut, spent a year bouncing around the cramped capsules of the ISS in an attempt to understand the long-term impact of space flight. He doesn’t hold the record for the most extended foray into the void – that is claimed by Gennady Padalka , who spent two and half years of his life up there on several missions – but the Kelly experiment had a natural advantage over others: he has a twin.

Comparing their bodies throughout, scientists were able to assess how bones, muscles and other parts of the body deteriorate in space. There is even a gym on the ISS where astronauts can keep their muscles – no longer needed to prop them up – from slowly wasting away. But they need to wear a harness to keep them from floating off the treadmill. One big issue is that eye problems develop, but Kelly found his body recovered fast on return. He and his twin seemed in similar shape – good news for future deep space missions.

Which countries have human space programmes?

Only three countries, China, Russia and the US, have human space programmes as it remains prohibitively expensive. However, they have provided lifts for space travellers from 40 countries, including a member of the Saudi royal family and even paying customers, such as South African millionaire Mark Shuttleworth, aged just 28.

How much does it cost to send them up?

Astronomical. The ISS is the most expensive machine ever constructed with a price tag at around $150bn (£115bn). Nasa’s space shuttle programme, which kicked off in the early 1970s by promising safe and affordable access to space, hoped to cost just a few tens of million dollars per launch. But as the shuttle was thrown in the scrapyard in 2011, the agency estimated the total cost at $209bn — nearly $1.6bn per flight.

Following the big fight over the shuttle, which looked fantastic but also restricted space adventuring to Earth’s orbit as well as costing a fortune, the US took a side seat in launches. Most astronauts are now sent by the Russian space agency, which sells round-trip rides on its Soyuz spacecraft for between $21m and $82m .

Is human space flight worth the cost?

Anyone involved in space travel will scoff at this, but it’s a good question, and space agencies often don’t communicate their achievements enough. Almost every sector of human progress has benefited from sending people into space. Just the act of attempting the feat forced scientists to invent new systems. The Apollo guidance computer was a predecessor to the microcomputer, now found in all smartphones. Clothes are more fire-resistant because of research on space fires . Remotely monitoring the health of astronauts has led to revolutionary systems for helping patients on Earth . Diseases behave and develop differently in microgravity, which assists scientists in finding cures.

Others say paying for human space flight pumps money into the economy, arguing that spin-off companies from space research and a growing commercial space industry generates seven to 14 times the cost of missions. And Nasa, the most significant global player, is not spending nearly as much as it used to. About $19bn is spent by the US government on its budget , roughly half a percent of all federal spending. During the early Apollo programme, that was between 4% and 5%.

How strong is space cooperation between countries?

The first space race was part of the chest-beating of the cold war, but since then human space exploration has been more about countries working together than against each other. The ISS is a massive collaboration between five space agencies (Nasa, Roscosmos, Japan’s Jaxa, the pan-European agency ESA and the Canadian Space Agency) and was assembled over a period of 13 years from 1998, slowly adding capsules like Lego.

A big exception to this is China, which has gone it alone with its space ambitions, never sending an astronaut to the ISS. In 2006, Beijing reportedly tested lasers against US imaging satellites in what appeared to be an attempt to blind or damage them, and US lawmakers later banned cooperation between Nasa and China’s state agency.

However, the future of any effective human space flight is certainly likely to be cooperative rather than antagonistic. Since 2011, national spaces agencies in 14 countries have attempted to coordinate their dreams into a single vision. The most recent plan, published in January this year , said they had agreed to “expand human presence into the solar system, with the surface of Mars as a common driving goal”.

We’re off to the red planet? Hurray!

Don’t start the countdown just yet. To get to Mars, most people in the human space flight community feel we need to first go back to the moon. “It’s the only logical step,” says Ian Crawford, professor of planetary science and astrobiology at Birkbeck, University of London. “I’m all in favour of sending people to Mars, but the technology, competence, the experience – I think it’s still out of reach”.

The moon has several advantages. It’s only three days away, rather than a several-month round trip to Mars, and has been touted as a location for a research station similar to the one in Antarctica. From their celestial laboratory, scientists could study the impact of radiation exposure and near-weightlessness on the body at a closer distance to Earth, but still within deep space, all while preparing for trips further afield.

So to the moon then?

Well. Not quite either. The Global Exploration Roadmap suggests first building a space station as an orbital base from which to send astronauts back and forth to the moon. This will look similar to the ISS except, instead of rushing around the Earth, it will orbit the moon.

Will we ever get to Mars?

It is a mammoth feat and it would be wise to expect serious delays. “Where we go in space is decided by a combination of what people would like to do and the reality of time and budgets,” says Henry Hertzfeld, director of the Space Policy Institute at George Washington University, Washington DC, and a former policy analyst at Nasa. “The idea of putting people on Mars has been around for a long time. If you read the policies, it is clearly a long-term vision without a date. But we probably are still lacking the technology to keep people for a long time in deep space.”

Who are the new contenders in human space flight?

The US and Russia have been giving way to new players. In 2003, China became the third country to put a person into orbit and India plans to follow in 2022. But the sector-changing impact is undoubtedly coming from the private space.

In what is being coined the “billionaire’s space race”, Elon Musk, founder of Telsa electric cars, Amazon CEO Jeff Bezos and Virgin boss Richard Branson all want to send private citizens to space. Their companies, SpaceX, Blue Origin and Virgin Galactic , are set on making human space travel cheaper.

They join a handful of commercial space flight companies that already work as contractors for national space agencies. Aerospace industry titans Boeing and Lockheed Martin send heavy launchers into space, but that costs at least $350m per launch – several times more expensive than SpaceX’s new $90m Falcon Heavy system.

SpaceX has around $10bn worth of launches already booked and saves costs through reusable spacecraft, where even the rocket boosters land themselves back on the ground and can be dusted off for reuse.

And while it is looking increasingly likely that the ISS will be defunded in the next decade, several private ventures are considering either taking over or rebuilding their own space stations.

What’s next?

As government agencies prioritise the moon, others are looking straight at Mars. Musk has said his life goal is to create a thriving Mars colony as a fail-safe for humanity in case of a catastrophic event on Earth, such as a nuclear war or Terminator-style artificial intelligence coup. For this, SpaceX is developing the Big Falcon Rocket (BFR), which he claims could send crewed flights to the red planet by mid-2020.

Musk says the BFR is partly inspired by Tintin’s rocket and will be the biggest ever made at close to 40 storeys high and capable of ferrying as many as 100 passengers per trip, depending on how much luggage they want to put in the hold.

As well as a healthy satellite launch business, SpaceX is raising money by selling tickets on the BFR for a trip, some would say a jolly, around the moon. Yusaku Maezawa , a Japanese fashion billionaire and art collector, is funding such a mission slated for 2023 and says he is going to invite artists with him for the week-long trip to re-engage the public in the wonder of our universe.

Further reading

An astronaut’s guide to life on Earth, Chris Hadfield

To space and back, Sally Ride

The Right Stuff, Tom Wolfe

The Martian, Andy Weir

Endurance: A year in space, a lifetime of discovery, Scott Kelly

• The briefing
• Richard Branson

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How Far Have We Gone into Space?

The farthest distance that people (and animals) have traveled into space is to (or around) the moon. However, when we consider other technology that has gone into space — without a person inside — we’ve gone much, much farther . Humans have sent out a number of these personless probes to explore and better understand space. These probes are controlled by NASA scientists on Earth.  

As of 2019, there are 5 probes that have explored parts of the Solar System and have also left the Solar System to explore farther into space. 

*these values will be larger with time because these probes are still active

In 1998, Voyager 1 became the craft that had  travel ed the farthest from the Sun —  a distance of 69 AU . That is the equivalent of 1.03159504 x 10^ 10 kilometers ( 6.41 x 10^ 9 miles). This is the same distance as traveling  to the moon almost 27,000 times.  As of 2019, it had traveled ~147 AU and has continued to send data back to Earth.  

Traveling in space takes a very long time. In fact, it took 26 years for Voyager 1 to arrive at the edge of the heliosphere. This is a region of space, kind of like a bubble, that is created by the sun and contains our solar system. Here is a timeline of Voyager 1 travel:

September, 1977 - launch

January, 1979 - arrived at Jupiter

August, 1980 - arrived at Saturn

February, 2003 - enter ed  termination shock, the inner layer of the heliosphere’s bubble

June, 2012 - enter ed  heliopause, the outer layer of the heliosphere’s bubble

March, 2013 - enter ed  interstellar space, the region beyond the heliosphere

You can track Voyager 1 here , including how far it has traveled, it s velocity, and what instruments it is currently using. 

Scientists estimate that Voyager 1 will have enough power to continue its mission until about 2025. This gives it more time to explore farther into space and send back data. If Voyager 1 functions until that time, it will mean this probe had a lifespan of 48 years.

If still intact, Voyager 1 is expected to enter the Oort Cloud in about 300 years. Scientists believe that the Oort Cloud is like a giant shell that wraps around the rest of the Solar System. It’s kind of like an even larger bubble surrounding the heliosphere. It may also be where many of the comets that we see in our solar system come from. But scientists have never sent a probe there before now, so we don’t yet know for sure.

Additional images via Wikimedia Commons. Pioneer spacecraft illustration by  NASA Ames.

Have a different answer or more to add to this one? Send it to us .

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A cosmic time machine: how the James Webb Space Telescope lets us see the first galaxies in the universe

Postdoctoral Research Fellow, Centre for Astrophysics and Supercomputing, Swinburne University of Technology

Disclosure statement

Sara Webb does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

Swinburne University of Technology provides funding as a member of The Conversation AU.

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It has been an exciting week with the release of breathtaking photos of our Universe by the James Webb Space Telescope (JWST). Images such as the one below give us a chance to see faint distant galaxies as they were more than 13 billion years ago.

It’s the perfect time to step back and appreciate our first-class ticket to the depths of the Universe and how these images allow us to look back in time.

These images also raise interesting points about how the expansion of the Universe factors into the way we calculate distances at a cosmological scale.

Modern time travel

Looking back in time might sound like a strange concept, but it’s what space researchers do every single day.

Our Universe is bound by the rules of physics, with one of the best-known “rules” being the speed of light. And when we talk about “light”, we’re actually referring to all the wavelengths across the electromagnetic spectrum, which travel at around a whooping 300,000 kilometres per second.

Light travels so fast that in our everyday lives it appears to be instantaneous. Even at these break-neck speeds, it still takes some time to travel anywhere across the cosmos.

When you look at the Moon, you actually see it as it was 1.3 seconds ago. It’s only a tiny peek back in time, but it’s still the past. It’s the same with sunlight, except the photons (light particles) emitted from the Sun’s surface travel just over eight minutes before they finally reach Earth.

Our galaxy, the Milky Way, spans 100,000+ light-years. And the beautiful newborn stars seen in JWST’s Carina Nebula image are 7,500 light-years away. In other words, this nebula as pictured is from a time roughly 2,000 years earlier than when the first ever writing is thought to have been invented in ancient Mesopotamia.

Anytime we look away from the Earth, we’re looking back in time to how things once were. This is a superpower for astronomers because we can use light, as observed throughout time, to try to puzzle together the mystery of our universe.

What makes JWST spectacular

Space-based telescopes let us see certain ranges of light that are unable to pass through Earth’s dense atmosphere. The Hubble space telescope was designed and optimised to use both ultraviolet (UV) and visible parts of the electromagnetic spectrum.

The JWST was designed to use a broad range of infrared light. And this is a key reason the JWST can see further back in time than Hubble.

Galaxies emit a range of wavelengths on the electromagnetic spectrum, from gamma rays to radio waves, and everything in between. All of these give us important information about the different physics occurring in a galaxy.

When galaxies are near us, their light hasn’t changed that much since being emitted, and we can probe a vast range of these wavelengths to understand what’s happening inside them.

But when galaxies are extremely far away, we no longer have that luxury. The light from the most distant galaxies, as we see it now, has been stretched to longer and redder wavelengths due to the expansion of the universe.

This means some of the light that would have been visible to our eyes when it was first emitted has since lost energy as the universe expanded. It’s now in a completely different region of the electromagnetic spectrum. This is a phenomenon called “ cosmological redshift ”.

And this is where the JWST really shines. The broad range of infrared wavelengths detectable by JWST allow it to see galaxies Hubble never could. Combine this capability with the JWST’s enormous mirror and superb pixel resolution, and you have the most powerful time machine in the known universe.

Read more: Two experts break down the James Webb Space Telescope's first images, and explain what we've already learnt

Light age does not equal distance

Using the JWST, we will be able to capture extremely distant galaxies as they were only 100 million years after the Big Bang – which happened around 13.8 billion years ago.

So we will be able to see light from 13.7 billion years ago. What’s about to hurt your brain, however, is that those galaxies are not 13.7 billion light-years away. The actual distance to those galaxies today would be ~46 billion light-years.

This discrepancy is all thanks to the expanding universe, and makes working on a very large scale tricky.

The universe is expending due to something called “ dark energy ”. It’s thought to be a universal constant, acting equally in all areas of space-time (the fabric of our universe).

And the more the universe expands, the greater the effect dark energy has on its expansion. This is why even though the universe is 13.8 billion years old, it’s actually about 93 billion light-years across.

We can’t see the effect of dark energy on a galactic scale (within the Milky Way) but we can see it over much greater cosmological distances.

Sit back and enjoy

We live in a remarkable time of technology. Just 100 years ago, we didn’t know there were galaxies outside our own. Now we estimate there are trillions, and we are spoilt for choice.

For the foreseeable future, the JWST will be taking us on a journey through space and time each and every week. You can stay up to date with the latest news as NASA releases it.

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How far do we travel through space every day?

Depending on the reference point, travelling through space can vary between 40,000km and 47 million km per day.

Dr Alastair Gunn

Asked by: Stephen Newman, Foley, Alabama

This apparently simple question impinges on a fundamental axiom of physics: that there is no universal reference frame. So, when talking about the motion of the Earth, we have to declare which object the motion is with respect to.

For example, at the Earth’s equator you travel approximately 40,000km a day with respect to the Earth’s centre. Each day, the Earth’s orbit takes you about 2.5 million kilometres with respect to the Sun’s centre. And each day, the Earth moves about 19 million kilometres with respect to the centre of the Milky Way.

Finally, the Earth is also travelling about 47 million kilometres per day with respect to the ‘cosmic microwave background’ (CMB) – the leftover radiation from the birth of the Universe – which is perhaps the best surrogate we have for a universal reference frame. Since the directions of all these velocities are always changing, it would be meaningless to add them together.

• How far would we need to travel to leave our Galaxy?
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The Farthest Visible Reaches of Space

About the image.

Current observations suggest that the Universe is about 13.7 billion years old. We know that light takes time to travel, so that if we observe an object that is 13 billion light years away, then that light has been traveling towards us for 13 billion years. Essentially, we are seeing that object as it appeared 13 billion years ago.

With every year that passes, our newest technology enables us to see further and further back.

The image used for this stop on our journey is the Hubble Ultra Deep Field (UDF). The UDF is one of the deepest views of the visible universe to date; certainly it was the deepest when it was originally created in in 2003-2004. There are approximately 10,000 galaxies in this view, which is a sort of "core sample" of a very narrow patch of sky near the constellation Fornax. The smallest, reddest galaxies in the image , of which there are about 100, are among the most distant known objects!

The UDF looks back approximately 13 billion years (approximately between 400 and 800 million years after the Big Bang ). Galaxies that existed in that time period would be very young and very different in structure and appearance than the grand spirals we see nearby today.

What is the Farthest Known Object From Earth?

In December of 2012, astronomers announced a Hubble Space Telescope discovery of seven primitive galaxies located over 13 billion light years away from us. The results are from survey of the same patch of sky known as the Ultra Deep Field (UDF). This survey, called UDF12, used Hubble's Wide Field Camera 3 to peer deeper into space in near- infrared light than any previous Hubble observation.

Why infrared? Because the Universe is expanding; therefore the farther back we look, the faster objects are moving away from us, which shifts their light towards the red. Redshift means that light that is emitted as ultraviolet or visible light is shifted more and more to redder wavelengths .

The extreme distance of these newly discovered galaxies means their light has been traveling to us for more than 13 billion years, from a time when the Universe was less than 4% of its current age.

Their discovery, which you can read more about in the NASA feature is exciting because it might give us an idea of how abundant galaxies were close to the era when astronomers think galaxies first started forming. ( Phil Plait has a good column about this discovery too.)

As of this writing it seems that one of the galaxies in this recent Hubble discovery may be a distance record breaker - it was observed 380 million years after the Big Bang, with a redshift of 11.9. This means the light from this galaxy (pictured below) left 13.3+ billion light years ago.

Just under a month ago, the current candidate was this object: a young galaxy called MACS0647-JD . It's only a tiny fraction of the size of our Milky Way - and was observed at 420 million years after the Big Bang, when the universe was 3 percent of its present age of 13.7 billion years. To spot this galaxy, astronomers used the powerful gravity from the massive galaxy cluster MACS J0647+7015 to magnify the light from the distant galaxy; this effect is called gravitational lensing.

Earlier in 2012, with the combined power of NASA's Spitzer and Hubble Space Telescopes, as well as the use of gravitational lensing, a team of astronomers spotted what might then have been the most distant galaxy ever seen. Light from this young galaxy, MACS1149-JD, was emitted when our 13.7-billion-year-old universe was just 500 million years old.

In 2010, a candidate for most distant galaxy was found in the Hubble Ultra Deep Field. UDFy-38135539 is thought to be 13.1 billion light years away. There is more information in this article on Phil Plait's blog. I've used his labeled images:

The objects in the Hubble Ultra Deep Field may well be the farthest known objects, but there are other contenders.

They include a galaxy called Abell 1835 IR1916, which was discovered in 2004, by astronomers from the European Southern Observatory using a near-infrared instrument on the Very Large Telescope. The object is visible to us because of gravitational lensing by the galaxy cluster Abell 1835, which is between this object and us. This galaxy is thought to be about 13.2 billion light years away, which means it would date to about 500 million years after the Big Bang. Note though, that this find has not been verified by other instruments - the Spitzer Space Telescope tried in 2006 without success.

Also in 2004, a team using both the Hubble Space Telescope and the Keck Observatory discovered a galaxy that is believed to be about 13 billion years away from us. It was found when observing the galaxy cluster Abell 2218. The light from the distant galaxy was visible because of gravitational lensing. The very distant object is the one circled. For more information, check out this press release .

Then there's the infrared James Webb Space Telescope. If you recall, Hubble has near infrared capability, but not mid-infrared, and for objects with very high redshifts, to see these most distant of objects would require a powerful telescope with mid-infrared capability. JWST will be able to see back to the first luminous objects to be born after the Big Bang.

In fact, one of JWST objectives is to look even further back, to just 200 million years after the Big Bang. One model of galaxy evolution has the first galaxies forming then and we need JWST to test this theoretical prediction!

(Note: JWST will be able to see these first galaxies without the aid of gravitational lensing; gravitational lensing might allow us to see them better, but would not necessarily let us see further back in time.)

Distance Information

Some of the most newly detected objects may be over 13 billion light years away, as derived from a standard model of the Universe. However, a powerful new generation of telescopes, like the James Webb Space Telescope, will be needed to confirm the suspected distances of these objects.

When 13 billion light years is translated into kilometers, there are a staggering number of zeros - it comes out to approximately 123,000,000,000,000,000,000,000 km.

As time progresses, so will our ability to see futher and further away - giving us insight on the very beginnings of the Universe's existence!

How do We Calculate Distances of This Magnitude?

At these distances, objects' redshifts are used, with and extension of Hubble's Law to the distant Universe. Here, we have to know the history of how rapidly the universe was expanding at each moment in time. This can be calculated from the amount of normal and dark matter and of dark energy. Try Prof. Wright's Javascript cosmology calculator at: http://www.astro.ucla.edu/~wright/CosmoCalc.html

For more information on Hubble's Law, please read the section on finding distances to the Nearest Superclusters .

Why Are These Distances Important To Astronomers?

Scientists have estimated the age of the Universe to be 13.73 billion years old (with an uncertainty of about 120 million years). When we observe an object that is 13 billion light years away, we are essentially observing it as it was 13 billion years ago, when the Universe was young. Being able to see and thus hopefully understand the early Universe is important to understanding how it was formed. If we see back far enough, perhaps we will catch a glimpse of the first galaxies as they were just forming. Perhaps we will someday be able to see the first starts forming. Could we see even further back than that? Only time (and technology) will tell!

Travel Time

At the rate of 17.3 km/sec (the rate Voyager is traveling away from the Sun), it would take around 225,000,000,000,000 years to reach this distance. At the speed of light , it would take 13 billion years!

How long does it take to get to Mars?

We explore how long it takes to get to Mars and the factors that affect a journey to the Red Planet.

• Distance to Mars
• Traveling at the speed of light

Fastest spacecraft so far

Mars travel time q&a with an expert.

• Travel time calculation problems
• Past mission's travel times

Additional resources

Ever wondered how long does it take to get to Mars? 

The answer depends on several factors, ranging from the position of Earth and Mars to the technology that would propel you there. According to NASA , a one-way trip to the Red Planet would take about nine months . If you wanted to make it a round-trip , all in all, it would take about 21 months as you will need to wait about three months on Mars to make sure Earth and Mars are in a suitable location to make the trip back home. 

We take a look at how long a trip to the Red Planet would take using available technology and explore some of the factors that would affect your travel time.

Related: Curiosity rover: 15 awe-inspiring photos of Mars (gallery) 

How far away is Mars?

To determine how long it will take to reach Mars, we must first know the distance between the two planets.

Mars is the fourth planet from the sun, and the second closest to Earth (Venus is the closest). But the distance between Earth and Mars is constantly changing as they travel around the sun .

In theory, the closest that Earth and Mars would approach each other would be when Mars is at its closest point to the sun (perihelion) and Earth is at its farthest (aphelion). This would put the planets only 33.9 million miles (54.6 million kilometers) apart. However, this has never happened in recorded history. The closest recorded approach of the two planets occurred in 2003 when they were only 34.8 million miles (56 million km) apart.

The two planets are farthest apart when they are both at their farthest from the sun, on opposite sides of the star. At this point, they can be 250 million miles (401 million km) apart.

The average distance between Earth and Mars is 140 million miles (225 million km).

Related: What is the temperature on Mars?

How long would it take to travel to Mars at the speed of light?

Light travels at approximately 186,282 miles per second (299,792 km per second). Therefore, a light shining from the surface of Mars would take the following amount of time to reach Earth (or vice versa):

• Closest possible approach: 182 seconds, or 3.03 minutes
• Closest recorded approach: 187 seconds, or 3.11 minutes
• Farthest approach: 1,342 seconds, or 22.4 minutes
• On average: 751 seconds, or just over 12.5 minutes

The fastest spacecraft is NASA's Parker Solar Probe , as it keeps breaking its own speed records as it moves closer to the sun. On Nov 21, 2021, the Parker Solar Probe reached a top speed of 101 miles (163 kilometers) per second during its 10th close flyby of our star, which translates to a phenomenal 364,621 mph (586,000 kph). According to a NASA statement , when the Parker Solar Probe comes within 4 million miles (6.2 million kilometers) of the solar surface in December 2024, the spacecraft's speed will top 430,000 miles per hour (692,000 kph)!

So if you were theoretically able to hitch a ride on the Parker Solar Probe and take it on a detour from its sun-focused mission to travel in a straight line from Earth to Mars, traveling at the speeds the probe reaches during its 10th flyby (101 miles per second), the time it would take you to get to Mars would be:

• Closest possible approach: 93 hours 
• Closest recorded approach: 95 hours  
• Farthest approach: 686 hours (28.5 days)  
• On average: 384 hours (16 days)  

We asked Michael Khan, ESA Senior Mission Analyst some frequently asked questions about travel times to Mars. 

Michael Khan is a Senior Mission Analyst for the European Space Agency (ESA). His work involves studying the orbital mechanics for journeys to planetary bodies including Mars.

How long does it take to get to Mars & what affects the travel time?

The time it takes to get from one celestial body to another depends largely on the energy that one is willing to expend. Here  "energy" refers to the effort put in by the launch vehicle and the sum of the maneuvers of the rocket motors aboard the spacecraft, and the amount of propellant that is used. In space travel, everything boils down to energy. Spaceflight is the clever management of energy.

Some common solutions for transfers to the moon are 1) the Hohmann-like transfer and 2) the Free Return Transfer. The Hohmann Transfer is often referred to as the one that requires the lowest energy, but that is true only if you want the transfer to last only a few days and, in addition, if some constraints on the launch apply. Things get very complicated from there on, so I won't go into details.

Concerning transfers to Mars, these are by necessity interplanetary transfers, i.e., orbits that have the sun as central body. Otherwise, much of what was said above applies: the issue remains the expense of energy. An additional complication lies in the fact that the Mars orbit is quite eccentric and also its orbit plane is inclined with respect to that of the Earth. And of course, Mars requires longer to orbit the sun than the Earth does. All of this is taken into account in a common type of diagram called the "pork chop plot", which essentially tells you the required dates of departure and arrival and the amount of energy required.

The "pork chop plot" shows the trajectory expert that opportunities for Mars transfers arise around every 25-26 months, and that these transfers are subdivided into different classes, one that is a bit faster, with typically around 5-8 months and the other that takes about 7-11 months. There are also transfers that take a lot longer, but I’m not talking about those here. Mostly, but not always, the second, slower one turns out to be more efficient energy-wise. A rule of thumb is that the transfer to Mars takes around as long as the human period of gestation, approximately 9 months. But that really is no more than an approximate value; you still have to do all the math to find out what applies to a specific date.

Why are journey times a lot slower for spacecraft intending to orbit or land on the target body e.g. Mars compared to those that are just going to fly by?

If you want your spacecraft to enter Mars orbit or to land on the surface, you add a lot of constraints to the design problem. For an orbiter, you have to consider the significant amount of propellant required for orbit insertion, while for a lander, you have to design and build a heat shield that can withstand the loads of atmospheric entry. Usually, this will mean that the arrival velocity of Mars cannot exceed a certain boundary. Adding this constraint to the trajectory optimisation problem will limit the range of solutions you obtain to transfers that are Hohmann-like. This usually leads to an increase in transfer duration.

The problems with calculating travel times to Mars

The problem with the previous calculations is that they measure the distance between the two planets as a straight line. Traveling through the farthest passing of Earth and Mars would involve a trip directly through the sun, while spacecraft must of necessity move in orbit around the solar system's star.

Although this isn't a problem for the closest approach, when the planets are on the same side of the sun, another problem exists. The numbers also assume that the two planets remain at a constant distance; that is, when a probe is launched from Earth while the two planets are at the closest approach, Mars would remain the same distance away over the length of time it took the probe to travel. 

Related: A brief history of Mars missions

In reality, however, the planets are moving at different rates during their orbits around the sun. Engineers must calculate the ideal orbits for sending a spacecraft from Earth to Mars. Like throwing a dart at a moving target from a moving vehicle, they must calculate where the planet will be when the spacecraft arrives, not where it is when it leaves Earth. 

It's also not possible to travel as fast as you can possibly go if your aim is to eventually orbit your target planet. Spacecraft need to arrive slow enough to be able to perform orbit insertion maneuvers and not just zip straight past their intended destination. 

The travel time to Mars also depends on the technological developments of propulsion systems.

According to NASA Goddard Space Flight Center's website, the ideal lineup for a launch to Mars would get you to the planet in roughly nine months. The website quotes physics professor Craig C. Patten , of the University of California, San Diego:

"It takes the Earth one year to orbit the sun and it takes Mars about 1.9 years (say 2 years for easy calculation) to orbit the sun. The elliptical orbit which carries you from Earth to Mars is longer than Earth's orbit but shorter than Mars' orbit. Accordingly, we can estimate the time it would take to complete this orbit by averaging the lengths of Earth's orbit and Mars' orbit. Therefore, it would take about one and a half years to complete the elliptical orbit.

"In the nine months it takes to get to Mars, Mars moves a considerable distance around in its orbit, about three-eighths of the way around the sun. You have to plan to make sure that by the time you reach the distance of Mar's orbit, Mars is where you need it to be! Practically, this means that you can only begin your trip when Earth and Mars are properly lined up. This only happens every 26 months. That is, there is only one launch window every 26 months."

The trip could be shortened by burning more fuel — a process not ideal with today's technology, Patten said.

Evolving technology can help to shorten the flight. NASA's Space Launch System (SLS) will be the new workhorse for carrying upcoming missions, and potentially humans, to the red planet. SLS is currently being constructed and tested, with NASA now targeting a launch in March or April 2022 for its Artemis 1 flight, the first flight of its SLS rocket.

Robotic spacecraft could one day make the trip in only three days. Photon propulsion would rely on a powerful laser to accelerate spacecraft to velocities approaching the speed of light. Philip Lubin, a physics professor at the University of California, Santa Barbara, and his team are working on Directed Energy Propulsion for Interstellar Exploration (DEEP-IN). The method could propel a 220-lb. (100 kilograms) robotic spacecraft to Mars in only three days, he said.

"There are recent advances which take this from science fiction to science reality," Lubin said at the 2015 NASA Innovative Advanced Concepts (NIAC) fall symposium . "There's no known reason why we cannot do this." 

How long did past missions take to reach Mars?

Here is an infographic detailing how long it took several historical missions to reach the Red Planet (either orbiting or landing on the surface). Their launch dates are included for perspective. 

Explore NASA's lunar exploration plans with their Moon to Mars overview . You can read about how to get people from Earth to Mars and safely back again with this informative article on The Conversation . Curious about the human health risks of a mission to the Red Planet? You may find this research paper of particular interest.  

Bibliography

• Lubin, Philip. " A roadmap to interstellar flight. " arXiv preprint arXiv:1604.01356 (2016). 
• Donahue, Ben B. " Future Missions for the NASA Space Launch System. " AIAA Propulsion and Energy 2021 Forum . 2021. 
• Srinivas, Susheela. " Hop, Skip and Jump—The Moon to Mars Mission. " (2019). 

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: [email protected].

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Nola Taylor Tillman is a contributing writer for Space.com. She loves all things space and astronomy-related, and enjoys the opportunity to learn more. She has a Bachelor’s degree in English and Astrophysics from Agnes Scott college and served as an intern at Sky & Telescope magazine. In her free time, she homeschools her four children. Follow her on Twitter at @NolaTRedd

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How far do we travel through the universe in our lifetimes?

17 July 2019

My wife told me I should get out more. I replied that I am just about to celebrate my 66th free trip around the sun. Can anyone tell me how far I have travelled in our galaxy during that time?

Emma Eales , Edinburgh, UK

Earth moves at about 30 kilometres per second around the sun. If you count this as your own journey, you will have travelled about 62 billion kilometres in 66 Earth years.

Herman D’Hondt , Sydney, Australia

The answer depends on what motions you include. The speed of the solar system around the galactic centre is about 230 kilometres per second. If you only include that, then you travel 7.26 billion kilometres per year, or 479 billion kilometres overall.

However, we should also add the distance Earth has travelled around the sun and the distance your London home has travelled around Earth (at a speed of about 0.465 kilometres per second). These are much smaller amounts, but combined they add almost 63 billion kilometres to the total.

Mike Follows , Sutton Coldfield, West Midlands, UK

The solar system sits some 26,500 light years from the galactic centre, about halfway along a spiral arm. We orbit the centre of the Milky Way about once every 240 million years.

However, the universe has been expanding ever since the big bang , about 13.8 billion years ago. All galaxies are moving away from each other at a speed proportional to the distance that separates them. We can’t measure our speed relative to our starting point because the universe has no centre or edge. If there were nothing to disturb this motion, we would be stationary relative to the radiation left over from the big bang , the cosmic microwave background radiation. However, we are careering towards the Leo and Virgo constellations, pulled there at more than 600 kilometres per second by a group of galaxies dubbed the Great Attractor . This is nearly three times the speed at which we orbit the centre of the Milky Way.

When we celebrate anniversaries, we really have moved on and we each have an absolutely unique trajectory on the fabric of space-time .

Hillary J. Shaw , Newport, Shropshire, UK

Though you will have travelled about 62.5 billion kilometres around the sun in 66 years, it is a tiny distance in stellar terms: less than 1 per cent of a light year, or around 0.2 per cent of the distance from the sun to the nearest other star.

If you want to “get out more” in stellar terms, consider inventing an antimatter drive that can take you up to 99.9 per cent of light speed (and decelerate again). The resulting time dilation will enable you to tour much of the galaxy within your lifetime. But do take your wife with you, as when you return to Earth it will be many tens of thousands of years later.

David Roffey , London, UK

Movement through space is a big problem for time travel . Assuming you can get past the trivial bit of transporting yourself 66 years into the past, you would then be trillions of kilometres from the spot on the planet that you started from.

You would probably end up in a galactic void, which wouldn’t be good, and you would also have a small but non-zero chance of ending up in the gravity well of a star – even less good.

To answer this question – or ask a new one – email [email protected] .

Questions should be scientific enquiries about everyday phenomena, and both questions and answers should be concise. We reserve the right to edit items for clarity and style. Please include a postal address, daytime telephone number and email address.

New Scientist Ltd retains total editorial control over the published content and reserves all rights to reuse question and answer material that has been submitted by readers in any medium or in any format.

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Is Time Travel Possible?

We all travel in time! We travel one year in time between birthdays, for example. And we are all traveling in time at approximately the same speed: 1 second per second.

We typically experience time at one second per second. Credit: NASA/JPL-Caltech

NASA's space telescopes also give us a way to look back in time. Telescopes help us see stars and galaxies that are very far away . It takes a long time for the light from faraway galaxies to reach us. So, when we look into the sky with a telescope, we are seeing what those stars and galaxies looked like a very long time ago.

However, when we think of the phrase "time travel," we are usually thinking of traveling faster than 1 second per second. That kind of time travel sounds like something you'd only see in movies or science fiction books. Could it be real? Science says yes!

This image from the Hubble Space Telescope shows galaxies that are very far away as they existed a very long time ago. Credit: NASA, ESA and R. Thompson (Univ. Arizona)

How do we know that time travel is possible?

More than 100 years ago, a famous scientist named Albert Einstein came up with an idea about how time works. He called it relativity. This theory says that time and space are linked together. Einstein also said our universe has a speed limit: nothing can travel faster than the speed of light (186,000 miles per second).

Einstein's theory of relativity says that space and time are linked together. Credit: NASA/JPL-Caltech

What does this mean for time travel? Well, according to this theory, the faster you travel, the slower you experience time. Scientists have done some experiments to show that this is true.

For example, there was an experiment that used two clocks set to the exact same time. One clock stayed on Earth, while the other flew in an airplane (going in the same direction Earth rotates).

After the airplane flew around the world, scientists compared the two clocks. The clock on the fast-moving airplane was slightly behind the clock on the ground. So, the clock on the airplane was traveling slightly slower in time than 1 second per second.

Credit: NASA/JPL-Caltech

Can we use time travel in everyday life?

We can't use a time machine to travel hundreds of years into the past or future. That kind of time travel only happens in books and movies. But the math of time travel does affect the things we use every day.

For example, we use GPS satellites to help us figure out how to get to new places. (Check out our video about how GPS satellites work .) NASA scientists also use a high-accuracy version of GPS to keep track of where satellites are in space. But did you know that GPS relies on time-travel calculations to help you get around town?

GPS satellites orbit around Earth very quickly at about 8,700 miles (14,000 kilometers) per hour. This slows down GPS satellite clocks by a small fraction of a second (similar to the airplane example above).

GPS satellites orbit around Earth at about 8,700 miles (14,000 kilometers) per hour. Credit: GPS.gov

However, the satellites are also orbiting Earth about 12,550 miles (20,200 km) above the surface. This actually speeds up GPS satellite clocks by a slighter larger fraction of a second.

Here's how: Einstein's theory also says that gravity curves space and time, causing the passage of time to slow down. High up where the satellites orbit, Earth's gravity is much weaker. This causes the clocks on GPS satellites to run faster than clocks on the ground.

The combined result is that the clocks on GPS satellites experience time at a rate slightly faster than 1 second per second. Luckily, scientists can use math to correct these differences in time.

If scientists didn't correct the GPS clocks, there would be big problems. GPS satellites wouldn't be able to correctly calculate their position or yours. The errors would add up to a few miles each day, which is a big deal. GPS maps might think your home is nowhere near where it actually is!

In Summary:

Yes, time travel is indeed a real thing. But it's not quite what you've probably seen in the movies. Under certain conditions, it is possible to experience time passing at a different rate than 1 second per second. And there are important reasons why we need to understand this real-world form of time travel.

If you liked this, you may like:

How Long Would It Take To Travel A Light Year

Using the fastest man-made vehicle, NASA’s Juno spacecraft, which travels at 165,000 mph (365,000 kmph), it would take 2,958 years to travel a light year. A light year is equivalent to about 5.88 trillion miles (9.46 trillion kilometers).

Traveling at the speed of light would be the fastest way to cover vast distances in space, but current technology makes it impossible for humans or even our most advanced spacecraft to reach this speed.

Can people match the speed of a light year?

According to Einstein, it is impossible to match the speed of light. It is because light is the fastest thing in the universe, traveling at 186,000 miles per second (300,000 kilometers per second). There is not one thing that we could invent that could even match a fraction of how fast light travels.

Some scientists have theorized that a new type of engine, called a warp drive , could potentially allow humans to reach the speed of travel required to match the speed of light. However, even if future spacecrafts were able to achieve this level of propulsion, it would still take thousands of years to travel from one star system to another.

Despite the challenges, scientists continue to study space travel at faster-than-light speeds, as they are optimistic that one day we will be able to explore the vast reaches of our universe and even discover life on other planets.

For now, it would take many thousands of years to travel a light year using current technology. However, scientists remain hopeful that one day we will be able to explore the far reaches of space and perhaps even discover other life forms in distant star systems. Until then, we can continue marveling at the

Related Posts:

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• How Long Would It Take To Get To Saturn?
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Light Year Calculator

What is light year, how to calculate light years.

With this light year calculator, we aim to help you calculate the distance that light can travel in a certain amount of time . You can also check out our speed of light calculator to understand more about this topic.

We have written this article to help you understand what a light year is and how to calculate a light year using the light year formula . We will also demonstrate some examples to help you understand the light year calculation.

A light year is a unit of measurement used in astronomy to describe the distance that light travels in one year . Since light travels at a speed of approximately 186,282 miles per second (299,792,458 meters per second), a light year is a significant distance — about 5.88 trillion miles (9.46 trillion km) . Please check out our distance calculator to understand more about this topic.

The concept of a light year is important for understanding the distances involved in space exploration. Since the universe is so vast, it's often difficult to conceptualize the distances involved in astronomical measurements. However, by using a light year as a unit of measurement, scientists and astronomers can more easily compare distances between objects in space.

As the light year is a unit of measure for the distance light can travel in a year , this concept can help us to calculate the distance that light can travel in a certain time period. Hence, let's have a look at the following example:

• Source: Light
• Speed of light: 299,792,458 m/s
• Time traveled: 2 years

You can perform the calculation in three steps:

Determine the speed of light.

The speed of light is the fastest speed in the universe, and it is always a constant in a vacuum. Hence, the speed of light is 299,792,458 m/s , which is 9.46×10¹² km/year .

Compute the time that the light has traveled.

The subsequent stage involves determining the duration of time taken by the light to travel. Since we are interested in light years, we will be measuring the time in years.

To facilitate this calculation, you may use our time lapse calculator . In this specific scenario, the light has traveled for a duration of 2 years.

Calculate the distance that the light has traveled.

The final step is to calculate the total distance that the light has traveled within the time . You can calculate this answer using the speed of light formula:

distance = speed of light × time

Thus, the distance that the light can travel in 100 seconds is 9.46×10¹² km/year × 2 years = 1.892×10¹³ km

How do I calculate the distance that light travels?

You can calculate the distance light travels in three steps:

Determine the light speed .

Determine the time the light has traveled.

Apply the light year formula :

distance = light speed × time

How far light can travel in 1 second?

The light can travel 186,282 miles, or 299,792,458 meters, in 1 second . That means light can go around the Earth just over 7 times in 1 second.

Why is the concept of a light year important in astronomy?

The concept of a light year is important in astronomy because it helps scientists and astronomers more easily compare distances between objects in space and understand the vastness of the universe .

Can light years be used to measure time?

No , despite the name, you cannot use light years to measure time. They only measure distance .

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Watch CBS News

Earthquake maps show where seismic activity shook the Northeast today

By Lucia Suarez Sang

Updated on: April 5, 2024 / 7:51 PM EDT / CBS News

Residents across the Northeast were rattled by a  4.8 magnitude earthquake that shook  the densely populated New York City metropolitan area and much of the surrounding region on Friday morning. The U.S. Geological Survey was quick to release maps showing the spot where the quake was centered, in New Jersey, and the area where it was felt.

The USGS reported the quake occurred about 7 miles north of Whitehouse Station, New Jersey. It indicated that the quake might have been felt by more than 42 million people. There were several aftershocks later in the day, including one with a magnitude of 4.0.

People in Baltimore , Philadelphia , New Jersey, Connecticut, Boston and other areas of the Northeast reported shaking. Tremors lasting for several seconds were felt over 200 miles away near the Massachusetts-New Hampshire border.

The map below shows the seismic intensity of the earthquake. The map, which is mostly a lighter shade of blue, shows that the intensity was light to weak, depending on the distance from the epicenter. 

Another map released by the European-Mediterranean Seismological Centre on X, formerly Twitter, highlights the eyewitness reports of shaking and possible damage levels during the seismic event. 

#Earthquake 18 mi W of #Plainfield (New Jersey) 23 min ago (local time 10:23:20). Updated map - Colored dots represent local shaking & damage level reported by eyewitnesses. Share your experience via: 📱 https://t.co/IbUfG7TFOL 🌐 https://t.co/wErQf69jIn pic.twitter.com/jBjVw1ngAD — EMSC (@LastQuake) April 5, 2024

New York Gov. Kathy Hochul and New York City Mayor Eric Adams have been briefed on the quake. 

"We're taking this extremely seriously and here's why: There's always the possibility of aftershocks. We have not felt a magnitude of this earthquake since about 2011," Hochul said. 

People across the region were startled by the rumbling of the quake. One New York City resident told CBS New York's Elijah Westbrook, "I was laying in my bed, and my whole apartment building started shaking. I started freaking out," 

It's not the first time the East Coast and New York City have been hit by an earthquake. 

A 5.0 quake was measured in New York City in 1884. 

The shaking stirred memories of the Aug. 23, 2011, earthquake that jolted tens of millions of people from Georgia to Canada. Registering magnitude 5.8, it was the strongest quake to hit the East Coast since World War II. The epicenter was in Virginia.

That earthquake left cracks in the Washington Monument, spurred the evacuation of the White House and Capitol and rattled New Yorkers three weeks before the 10th anniversary of the Sept. 11 terror attacks.

• New England
• Connecticut
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• United States Geological Survey
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Total solar eclipse April 8, 2024 facts: Path, time and the best places to view

In the U.S., 31 million people already live inside the path of totality.

Scroll down to see the list of U.S. cities where the April 8 total solar eclipse will be visible, the duration of the eclipse in those locations and what time totality will begin, according to GreatAmericanEclipse.com .

"Eclipse Across America," will air live Monday, April 8, beginning at 2 p.m. ET on ABC, ABC News Live, National Geographic Channel, Nat Geo WILD, Disney+ and Hulu as well as network social media platforms.

On April 8, 2024, a historic total solar eclipse will cast a shadow over parts of the United States, prompting a mass travel event to the path of totality -- from Texas to Maine and several states and cities in between.

A total solar eclipse occurs when the moon passes between the sun and the Earth and, for a short time, completely blocks the face of the sun, according to NASA .

The track of the moon's shadow across Earth's surface is called the path of totality, and to witness the April 8 total solar eclipse, viewers must be within the 115-mile-wide path. To discover when to see the solar eclipse in totality or the partial eclipse in locations across the U.S. outside of the path, check out NASA's Eclipse Explorer tool .

Eclipse travel

In the U.S., 31 million people already live inside the path of totality, bringing the celestial phenomenon to their doorsteps, Michael Zeiler, expert solar eclipse cartographer at GreatAmericanEclipse.com told ABC News.

MORE: Eclipse glasses: What to know to keep your eyes safe

But for individuals outside of the path, investing time and money are needed to experience the event in totality.

Eclipse chasers, or umbraphiles, are individuals who will do almost anything, and travel almost anywhere, to see totality, according to the American Astronomical Society .

"There's a very active community of solar eclipse chasers and we will go to any reasonable lengths to see solar eclipses anywhere in the world," Zeiler said. "All of us are united in pursuing the unimaginable beauty of a total solar eclipse."

MORE: The surprising reason why a Texas county issued a disaster declaration ahead of April total solar eclipse

Bringing together both eclipse experts and novice sky watchers, the total solar eclipse on April 8 is projected to be the U.S.'s largest mass travel event in 2024, according to Zeiler, who likened it to "50 simultaneous Super Bowls across the nation."

"When you look at the number of people expected to come to the path of totality for the solar eclipse, we estimate those numbers are roughly the equivalent of 50 simultaneous Super Bowls across the nation, from Texas to Maine," he said.

Eclipse map, path of totality

In the U.S., the path of totality begins in Texas and will travel through Oklahoma, Arkansas, Missouri, Illinois, Kentucky, Indiana, Ohio, Pennsylvania, New York, Vermont, New Hampshire and Maine. Small parts of Tennessee and Michigan will also experience the total solar eclipse, according to NASA.

Best times, places to view eclipse

Below is a list of some American cities where the April 8 total solar eclipse will be most visible -- pending weather forecasts -- the duration of the eclipse in those locations and what time totality will begin, according to GreatAmericanEclipse.com.

• Eagle Pass, Texas, 1:27 p.m. CDT: 4 minutes, 23 seconds
• Uvalde, Texas, 1:29 p.m. CDT: 4 minutes, 16 seconds
• Kerrville, Texas, 1:32 p.m. CDT: 4 minutes, 23 seconds
• Austin, Texas, 1:36 p.m. CDT: 1 minute, 53 seconds
• Killeen, Texas, 1:36 p.m. CDT: 4 minutes, 17 seconds
• Fort Worth, Texas, 1:40 p.m. CDT: 2 minutes, 34 seconds
• Dallas, Texas, 1:40 p.m. CDT: 3 minutes, 47 seconds
• Little Rock, Arkansas, 1:51 p.m. CDT: 2 minutes, 33 seconds
• Jonesboro, Arkansas, 1:55 p.m. CDT: 2 minutes, 24 seconds
• Poplar Bluff, Arkansas, 1:56 p.m. CDT: 4 minutes, 8 seconds
• Cape Girardeau, Missouri, 1:58 p.m. CDT: 4 minutes, 6 seconds
• Carbondale, Illinois, 1:59 p.m. CDT: 4 minutes, 8 seconds
• Mount Vernon, Illinois, 2:00 p.m. CDT: 3 minutes, 40 seconds
• Evansville, Indiana, 2:02 p.m. CDT: 3 minutes, 2 seconds
• Terre Haute, Indiana, 3:04 p.m. EDT: 2 minutes, 57 seconds
• Indianapolis, Indiana, 3:06 p.m. EDT: 3 minutes, 46 seconds
• Dayton, Ohio, 3:09 p.m. EDT: 2 minutes, 46 seconds
• Wapakoneta, Ohio, 3:09 p.m. EDT: 3 minutes, 55 seconds
• Toledo, Ohio, 3:12 p.m. EDT: 1 minute, 54 seconds
• Cleveland, Ohio, 3:13 p.m. EDT: 3 minutes, 50 seconds

Pennsylvania

• Erie, Pennsylvania, 3:16 p.m. EDT: 3 minutes, 43 seconds
• Buffalo, New York, 3:18 p.m. EDT: 3 minutes, 45 seconds
• Rochester, New York, 3:20 p.m. EDT: 3 minutes, 40 seconds
• Syracuse, New York, 3:23 p.m. EDT: 1 minute, 26 seconds
• Burlington, Vermont, 3:26 p.m. EDT: 3 minutes, 14 seconds
• Island Falls, Maine, 3:31 p.m. EDT: 3 minutes, 20 seconds
• Presque Island, Maine, 3:32 p.m. EDT: 2 minutes, 47 seconds

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4.8 magnitude earthquake rattles NYC, New Jersey: Live updates

NEW YORK – A 4.8 magnitude earthquake recorded in New Jersey that shook residents in surrounding states and New York City on Friday morning was one of the strongest in state history.

The temblor was reported about 5 miles north of Whitehouse Station, New Jersey, at about 10:23 a.m. Friday, according to the United States Geological Survey. The epicenter was about 45 miles from New York City, where residents reported shaking furniture and floors.

“Earthquakes in this region are uncommon but not unexpected. It’s likely people near the epicenter are going to feel aftershocks for this earthquake in the magnitude 2-3 range, and there’s a small chance there can be an earthquake as large or larger, following an earthquake like this,” Paul Earle, a seismologist at the USGS Earthquake Hazards Program told reporters. “In terms of our operations, this is a routine earthquake … Immediately we knew this would be of high interest and important to people who don’t feel earthquakes a lot.”

People reported feeling the shaking as far north as Maine and as far south as Norfolk, Virginia, following the quake, according to USGS. Scientists said those in the affected area should listen to local emergency officials and be prepared to seek cover if aftershocks occur.

“If you feel shaking, drop, cover and hold,” Earle said.

No major disruptions or damage have been reported in New Jersey or New York.

"We have activated our State Emergency Operations Center. Please do not call 911 unless you have an actual emergency," said New Jersey Gov. Phil Murphy.

President Joe Biden spoke with Murphy about the earthquake and the White House is monitoring the situation.

“He thinks everything's under control,” Biden told reporters before leaving the White House for a trip to Baltimore. “He’s not too concerned about it, the governor of New Jersey, so things are all right.”

New York Gov. Kathy Hochul said the quake was felt throughout New York, and officials are assessing impacts and any potential damage.

In Yonkers, New York, Mayor Mike Spano said City Hall shook but no injuries were reported.

"A few moments ago our entire house shook for about 25 seconds or so here in Mendham, New Jersey," former New Jersey Gov. Chris Christie said.

USGS is still investigating the exact fault line at the center of Friday’s quake and said it occurred in a region with dozens of fault lines that were more active millions of years ago.

4.0 magnitude aftershock strikes hours after earthquake

Officials in New York and New Jersey alerted residents to an aftershock Monday evening, nearly eight hours after the earthquake.

A 4.0 magnitude aftershock slammed New Jersey at around 6 p.m., with an epicenter about four miles southwest of Gladstone, according to the USGS. New York City’s emergency notification system alerted residents to the aftershock minutes later, urging people to remain indoors and call 911 if injured.

Hochul said there were no reports of serious damage after the aftershock, and officials were continuing to assess critical infrastructure.

The aftershock Monday evening was at least the third that USGS recorded after the quake struck.

As of Friday afternoon, the USGS aftershock forecast predicted a 36% chance of aftershocks at a 3.0 magnitude or higher, an 8% chance of aftershocks at a 4.0 magnitude or higher, and a 1% chance for aftershocks at a magnitude of 5.0 or higher over the next week.

USGS scientists said informal observations can be a big help in understanding earthquakes, especially in a region where they’re less common.

“We encourage people to fill out the ‘Did You Feel It?’ reports on our website,” said Sara McBride, a scientist with the USGS Earthquake Hazards Program. “This citizen science project is critical in terms of building our knowledge around earthquakes.”

By midafternoon on Friday, the agency said it had received more than 161,000 reports, and extrapolated that the quake had been felt by millions of people. McBride acknowledged that earthquakes can be nerve-wracking for people who don’t live in seismologically active regions, and said knowledge is power in combatting that discomfort.

“The best thing you can do to relieve any unsettling feelings you might have is to learn how to protect yourself during shaking and how to prepare for earthquakes in the future,” she said.

Man getting vasectomy during earthquake recounts experience

One Horsham, Pennsylvania, man shared his unusual earthquake experience, saying the tremors hit when he was in the middle of receiving a vasectomy.

"The surgeon sort of froze and all of us kind of seemed a bit confused," Justin Allen told USA TODAY . "Even when the surgeon said 'that’s gotta be an earthquake,' I thought he was joking."

Luckily, Allen's doctor was able to resume the procedure after a brief pause, and the rest went off without a hitch. Now recovering at home, Allen said it's an experience no one involved will forget, especially because his social media post about the incident has since gone viral.

"My wife says that 'this is a clear and obvious sign that we should not have any more kids,'" Allen said.

New Jersey resident thought sound from earthquake was an explosion

Madeline Nafus had just finished feeding her 7-week-old baby when, simultaneously, she was thrown off balance and the loudest sound she’d ever heard rang out.

“I thought it was either an explosion or a bombing because of how loud it was,” said Nafus, who lives in Long Valley, New Jersey, a few miles from the earthquake's epicenter. “It was just terrifying.”

Nafus, 29, watched as her light fixtures swung and wine glasses, framed photos and a 6-foot elk head crashed onto the floor. Feeling as if her “house was going to crumble,” she picked up her baby boy, grabbed some blankets and headed outside. Meanwhile, her friend came running downstairs and picked up Nafus’ quivering dog, Olivia, a small golden doodle.

After about 15 seconds, the rumbling went away and only occasional, minor tremors could be felt. Nafus called her husband, who was teaching a golf lesson at the time, and then their 2-year-old’s day care.

“They said the children were all confused and asking a lot of questions but that they were OK,” she said.'

How common are East Coast quakes?

Earthquakes are less frequent in the eastern part of the country than in the west, but they have occurred in every state east of the Mississippi River, according to the USGS.

"Since colonial times people in the New York – Philadelphia – Wilmington urban corridor have felt small earthquakes and suffered damage from infrequent larger ones," according to the USGS. "Moderately damaging earthquakes strike somewhere in the urban corridor roughly twice a century, and smaller earthquakes are felt roughly every two to three years."

USGS officials also said that even smaller-magnitude quakes are more likely to be felt more widely on the East Coast than similar size quakes on the West Coast due to the rock properties of eastern soil, which can cause concern to East Coasters not used to the tremors.

Rocks in the eastern part of the country are much older than in the west, by up to millions of years. Those older rocks have been exposed to more extreme temperatures and pressure, and faults have had more time to heal. Seismic waves travel across the resulting harder and denser faults much more efficiently, so the effects of a quake are felt across a larger area. In the West, faults are newer and absorb more of the seismic wave energy without spreading as far.

Quake felt in Massachusetts

In Auburn, Massachusetts, more than 200 miles from the earthquake's epicenter, Jerry Steinhelper was on a video call for work when his house began to tremble. His dog Maize started barking, and books and trinkets fell from their shelves. He looked out the window and saw trees shaking.

“I thought at first it may be ice falling off the roof. But it kept going and the entire house was shaking,” he told USA TODAY. “Then I just knew it was an earthquake.”

Steinhelper, 55, lived in San Diego in the 1980s and experienced temblors there, but he’s never felt one in Massachusetts, where he’s been for over 25 years.

“It was an interesting 10 to 15 seconds,” he said.

'It felt like a plane crashed outside' near epicenter

Nicole Kravitz, 33, was baking muffins at the cafe she co-owns with her husband in New Jersey when the floor began to shake. She and the cooks looked at each other for a few moments, and then at some stacked plates and glasses that had started vibrating.

Their eatery, Branchburg's Best, is located in New Jersey's Somerset County, near the epicenter of Friday’s earthquake.

“It felt like a plane crashed outside,” she said. “No one knew what was happening.”

Some workers ran out the door to see if something had smashed into the building while she checked the basement for damage. Meanwhile, Patrick Tucker, her husband, who was picking up beef from a nearby farm, watched agitated chickens and cows run around in their pens, visibly shaken by the quake.

Kravitz said the intensity of the earthquake made her feel like she was back in Southern California, where she had lived for several years before she returned to her home state in 2016.

Quake was one of the strongest to ever impact New Jersey

Friday's earthquake was the most significant in New Jersey since 1884 , when an Aug. 10 earthquake somewhere near Jamaica Bay, New York, toppled chimneys and moved houses off their foundations as far as Rahway, New Jersey, 30 miles away.

Other than that quake, there were only  three earthquakes in modern history  that caused damage in the state: 1737 (New York City), 1783 (west of New York City) and 1927 (New Jersey coast near Asbury), according to New Jersey Office of Emergency Management records.

The Dec. 19, 1737 earthquake is believed by modern experts to have been a 5.2 magnitude quake. Charted as taking place in the greater New York City area, some accounts say its epicenter was near Weehawken. State records show it threw down chimneys. Chimneys were also hurled down during the Nov. 29, 1783 quake. Estimated at a 5.3 magnitude that originated in modern-day Rockaway Township, according to state records, it was felt from Pennsylvania to New England.

The Aug. 10, 1884 quake, estimated at a 5.2 magnitude was the last the state has seen of its significance and was felt from Virginia to Maine, according to state records.

  Read more about New Jersey's earthquake history.

– David M. Zimmer, NorthJersey.com

New Jersey business owner describes worst quake ever felt but went right back to work

It was a busy day for La Bella Salon & Spa in Lebanon, New Jersey, when an earthquake struck near the rural township.

About a dozen stylists and customers, some whom were getting their hair dyed while others got manicures and eyelash extensions, all froze as the building rattled for about 30 seconds.

“People started to feel the shaking, and it got worse and worse. We were like ‘Oh, my god, what is going on?’" said shop owner Rosanne Drechsel. “I thought a truck hit the building or something.”

After the tremor subsided, nearly everyone in the building started receiving texts and phone calls from friends and family, Drechsel, 61, said.

Nothing was damaged and no one was injured, but Drechsel, who was born and raised in New Jersey, said it was “by far the worst earthquake” she had ever felt.

“We all went back to work and finished the appointments,” she said. “Customers are calling now to see if we're still open and if they can still make their appointments later on today.”

'It was scary': Quake rattles shelves in Brooklyn bodega

In Brooklyn, residents said they felt their buildings shake and many went outdoors after the rumbling stopped to check in with neighbors.

Julio Melo, a deli worker, said he thought the sounds of the earthquake resembled those of a large truck going down the street. But when Melo, 32, looked around and saw beer bottles rattling on store shelves, and a potted plant shimmy down the counter, he thought it might be something bigger, he told USA TODAY.

“I looked at my employee and he had the same tragic face on as me, it was scary,” he said at Jenesis’ Grocery Corp. in Brooklyn’s Bedford-Stuyvesant neighborhood.

– Claire Thornton

Where was the earthquake felt?

Residents and officials said the earthquake was felt throughout New York, as well as in New Jersey, Connecticut, Pennsylvania and elsewhere. It was also felt as far away as Cambridge, Massachusetts, about 250 miles away from the reported epicenter.

Charita Walcott, a 38-year-old resident in the Bronx borough of New York, said the quake felt "like a violent rumble that lasted about 30 seconds or so."

"It was kind of like being in a drum circle, that vibration," she said.

Earthquakes common in the region, but the size is unusual: Expert

Chuck Ver Straeten, a geologist and curator of sedimentary rocks at the New York State Museum, told USA TODAY it’s not surprising this earthquake happened where it did.

“New York, around New York City going into New Jersey, there’s a lot of earthquakes historically down there. Happens every year,” he said. But it’s less common for them to be of such a high magnitude. It’s not surprising that many people felt it, he said. Usually, earthquakes in the region are at a lower magnitude and less likely to be felt.

Ver Straeten said the real question now is if this is just a precursor to a larger quake.

“You never know what is the earthquake, what is a pre-earthquake, what is an earthquake happening after the main earthquake, you just have to see,” he said. “One slip along the rock fault, when one happens, it makes other areas around there more tense also and they start to slip and you slip again and slip again.”

But, he added, it would be unlikely for a larger quake to follow this one. In the Northeast, it’s more common for one large quake to be followed by smaller aftershocks, rather than a mounting series of tremors. 

What does magnitude mean in an earthquake?

Magnitude is a measurement of the strength of an earthquake . Officially it's called the Moment Magnitude Scale . It's a logarithmic scale , meaning each number is ten times as strong as the one before it. So a 5.2 earthquake is moderate while a 6.2 is strong.

The magnitude and effect of an earthquake, according to Michigan Technological University :

◾ Below 2.5: Generally not felt

◾ 2.5 to 5.4: Minor or no damage

◾ 5.5 to 6.0: Slight damage to buildings

◾ 6.1 to 6.9: Serious damage

◾ 8.0 or greater: Massive damage, can totally destroy communities

Intensity scales, measured in Roman numerals, are used to describe how strong the earthquake felt to people in the area.

According to the California Earthquake Authority , an intensity of I is typically felt only under especially favorable conditions. A IV, which leads to light shaking, is felt indoors by many, but not typically outdoors. It might awaken some people at night and lead to a sensation like a truck striking a building. A parked car would rock. Intensities VI and above would be strong, frightening and felt by all, with the damage increasing up to a X where the shaking would be violent. Some well-built wooden structures would be destroyed and most masonry and frame structures along with their foundations would be ruined.

While you might have heard the term " the Richter Scale " used to describe earthquakes, it is no longer commonly used because it was only valid for certain earthquake frequencies and distance ranges.

This is a developing story and will be updated.

Contributing: Reuters

Strong Taiwan Quake Kills 9, Injures Hundreds

The earthquake was the most powerful to hit the island in 25 years. Dozens of people remained trapped, and many buildings were damaged, with the worst centered in the city of Hualien.

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• Hualien, Taiwan A landslide after the quake. Lam Yik Fei for The New York Times
• New Taipei City, Taiwan Books flew off shelves as a home shook. @Abalamindo via Storyful
• Taipei, Taiwan Passengers waiting at a train station as some services were suspended. Chiang Ying-Ying/Associated Press
• Hualien, Taiwan People are rescued from a building that had partially collapsed. TVBS via Associated Press
• Hualien, Taiwan Firefighters rescuing trapped residents from a building. CTI News via Reuters
• Taipei, Taiwan Students evacuated to a school courtyard after the earthquake. Lam Yik Fei for The New York Times
• Guishan Island, Taiwan Rocks tumbling down one side of an island popular for hiking. Lavine Lin via Reuters
• Hualien, Taiwan A building leaned to one side after the quake. Randy Yang via Associated Press
• Ishigaki, Okinawa, Japan Watching news on a rooftop of a hotel after a tsunami warning. Chang W. Lee/The New York Times
• Hualien, Taiwan Motorbikes damaged in the quake. TVBS via Associated Press
• New Taipei City, Taiwan Damage in an apartment Fabian Hamacher/Reuters
• New Taipei City, Taiwan Water cascading down a building during the quake. Wang via Reuters

Meaghan Tobin and Victoria Kim

Here’s what you need to know about the earthquake.

Taiwan was rocked Wednesday morning by the island’s strongest earthquake in a quarter century, a magnitude 7.4 tremor that killed at least nine people, injured more than 800 others and trapped dozens of people.

The heaviest damage was in Hualien County on the island’s east coast, a sleepy, scenic area prone to earthquakes. Footage from the aftermath showed a 10-story building there partially collapsed and leaning heavily to one side, from which residents emerged through windows and climbed down ladders, assisted by rescuers. Three hikers were killed after being hit by falling rocks on a hiking trail in Taroko National Park, according to the county government.

By late afternoon, officials said rescue efforts were underway to try to rescue 127 people who were trapped, many of them on hiking trails in Hualien.

One building in Changhua County, on the island’s west coast, collapsed entirely. The quake was felt throughout Taiwan and set off at least nine landslides, sending rocks tumbling onto Suhua Highway in Hualien, according to local media reports. Rail services were halted at one point across the island.

The earthquake, with an epicenter off Taiwan’s east coast, struck during the morning commute, shortly before 8 a.m. Taiwanese authorities said by 3 p.m., more than 100 aftershocks, many of them stronger than magnitude 5, had rumbled through the area.

In the capital, Taipei, buildings shook for over a minute from the initial quake. Taiwan is at the intersection of the Philippine Sea tectonic plate and the Eurasian plate, making it vulnerable to seismic activity. Hualien sits on multiple active faults, and 17 people died in a quake there in 2018.

Here is the latest:

The earthquake hit Taiwan as many people there were preparing to travel for Tomb Sweeping Day, a holiday across the Chinese-speaking world when people mourn the dead and make offerings at their graves. Officials warned the public to stay away from visiting tombs in mountain areas as a precaution, especially because rain was forecast in the coming days.

TSMC, the world’s biggest maker of advanced semiconductors, briefly evacuated workers from its factories but said a few hours later that they were returning to work. Chip production is highly precise, and even short shutdowns can cost millions of dollars.

Christopher Buckley

Lai Ching-te, Taiwan’s vice president, who is also its president-elect, visited the city of Hualien this afternoon to assess the destruction and the rescue efforts, a government announcement said. Mr. Lai, who will become president in May, said the most urgent tasks were rescuing trapped residents and providing medical care. Next, Mr. Lai said, public services must be restored, including transportation, water and power. He said Taiwan Railway’s eastern line could be reopened by Thursday night.

Meaghan Tobin

Taiwan’s fire department has updated its figures, reporting that nine people have died and 934 others have been injured in the quake. Fifty-six people in Hualien County remain trapped.

Shake intensity

Taiwan’s fire department reports that nine people have died and 882 others have been injured in Taiwan. In Hualien County, 131 people remain trapped.

Agnes Chang

Footage shows rocks tumbling down one side of Guishan Island, a popular spot for hiking known as Turtle Island, off the northeast coast of Taiwan. Officials said no fishermen or tourists were injured after the landslide.

The death toll has risen to nine, according to Taiwan government statistics.

Meaghan Tobin, Siyi Zhao

Officials in Taiwan warned residents to not visit their relatives' tombs, especially in the mountains, this weekend during the holiday, known as Ching Ming, meant to honor them. There had already been 100 aftershocks and the forecast called for rain, which could make travel conditions on damaged roads more treacherous.

Crews are working to reach people trapped on blocked roads. As of 1 p.m. local time, roads were impassable due to damage and fallen rock in 19 places, according to the Ministry of Transportation. At least 77 people remain trapped. A bridge before Daqingshui Tunnel appeared to have completely collapsed.

Taiwan’s worst rail disaster in decades — a train derailment in 2021 that killed 49 people — took place on the first day of the Tomb Sweeping holiday period that year, in the same region as the earthquake.

The earthquake hit Taiwan as many people here were preparing to travel for Tomb Sweeping Day, or Ching Ming, a day across the Chinese-speaking world when people mourn their dead, especially by making offerings at their graves. Now those plans will be disrupted for many Taiwanese.

The holiday weekend would typically see a spike in travel as people visit family across Taiwan. Currently, both rail transport and highways are blocked in parts of Hualien, said Transport Minister Wang Guo-cai. Work is underway to restore rail transportation in Hualien, and two-way traffic is expected to be restored at noon on Thursday, he said.

Taiwan’s preparedness has evolved in response to past quakes.

Taiwan’s earthquake preparedness has evolved over the past few decades in response to some of the island’s largest and most destructive quakes .

In the years after a 7.6 magnitude earthquake in central Taiwan killed nearly 2,500 people in 1999, the authorities established an urban search-and-rescue team and opened several emergency medical operation centers, among other measures .

And in 2018, after a quake in the eastern coastal city of Hualien killed 17 people and caused several buildings to partially collapse, the government ordered a wave of building inspections .

Taiwan has also been improving its early warning system for earthquakes since the 1980s. And two years ago, it rolled out new building codes that, among other things, require owners of vulnerable buildings to install ad-hoc structural reinforcements.

So how well prepared was Taiwan when a 7.4 magnitude quake struck near Hualien on Wednesday morning, killing at least seven people and injuring hundreds more?

Across the island, one building collapsed entirely, 15 others were in a state of partial collapse and another 67 were damaged, the island’s fire department said on Wednesday afternoon . Structural engineers could not immediately be reached for comment to assess that damage, or the extent to which building codes and other regulations might have either contributed to it or prevented worse destruction.

As for search-and-rescue preparedness, Taiwan is generally in very good shape, said Steve Glassey, an expert in disaster response who lives in New Zealand.

“ The skill sets, the capabilities, the equipment, the training is second to none,” said Dr. Glassey, who worked with Taipei’s urban search-and-rescue team during the response to a devastating 2011 earthquake in Christchurch, New Zealand. “They’re a very sharp operation.”

But even the best urban search-and-rescue team will be stretched thin if an earthquake causes multiple buildings to collapse, Dr. Glassey said.

Taiwan has options for requesting international help with search-and-rescue efforts. It could directly ask another country, or countries, to send personnel. And if multiple teams were to get involved, it could ask the United Nations to help coordinate them, as it did after the 1999 earthquake.

Pierre Peron, a spokesman for the United Nations, said on Wednesday afternoon that no such request had yet been made as a result of the latest earthquake.

Meaghan Tobin contributed reporting.

At least seven people have died and 736 have been injured as a result of the earthquake, according to Taiwan’s fire department. Another 77 people remained trapped in Hualien County, many of them on hiking trails. Search and rescue operations are underway, said the fire department.

Aftershocks of magnitudes between 6.5 and 7 were likely to occur over the next three or four days, said Wu Chien-fu, director of the Taiwanese Central Weather Administration’s Seismology Center, at a news conference.

As of 2 p.m., 711 people had been injured across Taiwan, the fire department said, and 77 people in Hualien County remained trapped. The four who were known to have died were in Hualien.

Victoria Kim

Hualien County is a quiet and scenic tourist destination.

Hualien County on Taiwan’s east coast is a scenic, sleepy tourist area tucked away from the island’s urban centers, with a famous gorge and aquamarine waters. It also happens to sit on several active faults , making it prone to earthquakes.

The county has a population of about 300,000, according to the 2020 census, about a third of whom live in the coastal city of Hualien, the county seat. It is one of the most sparsely populated parts of Taiwan. About three hours by train from the capital, Taipei, the city describes itself as the first place on the island that’s touched by the sun.

Hualien County is home to Taroko National Park, one of Taiwan’s most popular scenic areas. Visitors come to explore the Taroko Gorge, a striated marble canyon carved by the Liwu River, which cuts through mountains that rise steeply from the coast. The city of Hualien is a popular destination as a gateway to the national park.

According to the state-owned Central News Agency, three hikers were trapped on a trail near the entrance to the gorge on Wednesday, after the quake sent rocks falling. Two of them were found dead, the news agency said. Administrators said many roads within the park had been cut off by the earthquake, potentially trapping hikers, according to the report.

Earthquakes have rattled Hualien with some regularity. In 2018, 17 people were killed and hundreds of others injured when a magnitude 6.5 quake struck just before midnight, its epicenter a short distance northeast of the city of Hualien.

Many of the victims in that quake were in a 12-story building that was severely tilted, the first four floors of which were largely crushed, according to news reports from the time. The next year, the area was shaken by a 6.1-magnitude earthquake that injured 17 people.

The area has some of the highest concentrations of Taiwan’s aboriginal population, with several of the island’s Indigenous tribes calling the county home .

The county government in Hualien released a list of people that had been hospitalized with injuries, which stood at 118 people as of midday Wednesday.

Across Taiwan, one building fell down entirely, in Changhua County on the west coast, and 15 buildings partially collapsed, Taiwan’s fire department said. Another 67 buildings were damaged. One of the partially collapsed structures was a warehouse in New Taipei City where four people were rescued, according to Taiwan’s Central News Agency. Another 12 were rescued at a separate New Taipei City building where the foundation sank into the ground.

Peggy Jiang, who manages The Good Kid, a children’s bookstore down the street from the partially collapsed Uranus Building in Hualien, said it was a good thing they had yet to open when the quake struck. The area is now blocked off by police and rescue vehicles. “Most people in Hualien are used to earthquakes,” she said. “But this one was particularly scary, many people ran in the street immediately afterward.”

Lin Jung, 36, who manages a shop selling sneakers in Hualien, said he had been at home getting ready to take his 16-month-old baby to a medical appointment when the earthquake struck. He said it felt at first like a series of small shocks, then “suddenly it turned to an intense earthquake shaking up and down.” The glass cover of a ceiling lamp fell and shattered. “All I could do was protect my baby.”

Chris Buckley ,  Paul Mozur ,  Meaghan Tobin and John Yoon

The earthquake damaged buildings and a highway in Hualien.

The magnitude 7.4 earthquake that struck Taiwan on Wednesday damaged many buildings and a major highway in Hualien, a city on the eastern coast, and it knocked out power as it rocked the island.

Across Taiwan, the quake and its aftershocks caused one building to completely collapse and 15 others to partially collapse, according to Taiwan’s fire department. Sixty-seven other buildings sustained damage.

Two tall buildings in Hualien that sustained particularly extensive damage were at the center of the rescue efforts there. Most damage across the city was not life-threatening, said Huang Hsuan-wan, a reporter for a local news site.

Where buildings were reported damaged in Hualien City

“A lot of roads were blocked off. There are a lot of walls toppled over onto cars,” Derik du Plessis, 44, a South African resident of Hualien, said shortly after the earthquake. He described people rushing around the city to check on their houses and pick up their children. One of his friends lost her house, he said.

One of the damaged buildings in Hualien, a 10-story structure called the Uranus Building that housed a mix of homes and shops, was tilted over and appeared to be on the verge of collapse. Many of its residents managed to flee, but some were missing, said Sunny Wang, a journalist based in the city. Rescuers were trying to reach the basement, concerned that people might be trapped there.

Photographs of the initial damage in Hualien showed another building, a five-story structure, leaning to one side, with crushed motorcycles visible at the ground-floor level. Bricks had fallen off another high-rise, leaving cracks and holes in the walls.

The quake also set off at least nine landslides on Suhua Highway in Hualien, according to Taiwan’s Central News Agency, which said part of the road had collapsed.

Taiwan’s fire department said four people had been killed in the earthquake.

Across Taiwan, 40 flights have been canceled or delayed because of the earthquake, according to Taiwan’s Central Emergency Operation Center.

President Tsai Ing-wen visited Taiwan’s national emergency response center this morning, where she was briefed about the response efforts underway by members of the ministries of defense, transportation, economic affairs and agriculture, as well as the fire department.

A look at Taiwan’s strongest earthquakes.

The magnitude 7.4 earthquake that hit Taiwan on Wednesday morning was the strongest in 25 years, the island’s Central Weather Administration said.

At least four people died after the quake struck off Taiwan’s east coast, officials said.

Here’s a look back at some of the major earthquakes in modern Taiwanese history:

Taichung, 1935

Taiwan’s deadliest quake registered a magnitude of 7.1 and struck near the island’s west coast in April 1935, killing more than 3,200 people, according to the Central Weather Administration. More than 12,000 others were injured and more than 50,000 homes were destroyed or damaged.

Tainan, 1941

A magnitude 7.3 earthquake in December 1941, which struck southwestern Taiwan, caused several hundred deaths, the United States Geological Survey said.

Chi-Chi, 1999

A 7.6 magnitude earthquake in central Taiwan killed nearly 2,500 people in September 1999. The quake, which struck about 90 miles south-southwest of Taipei, was the second-deadliest in the island’s history, according to the U.S.G.S. and the Central Weather Administration. More than 10,000 people were injured and more than 100,000 homes were destroyed or damaged.

Yujing, 2016

A 6.4 magnitude earthquake in February 2016 caused a 17-story apartment complex in southwestern Taiwan to collapse, killing at least 114 people . The U.S.G.S. later said that 90 earthquakes of that scale or greater had occurred within 250 kilometers, or 155 miles, of that quake’s location over the previous 100 years.

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Rare 4.8 magnitude quake rattles Northeast

By Elise Hammond , Leinz Vales and Matt Meyer , CNN

Why mild East Coast earthquakes are felt over such long distances

From CNN's David Goldman

Did you feel that?

It wasn't just folks in Western New Jersey who were texting "what was that?" messages in the mid-morning Friday. People as far away as Maryland and Upstate New York reported feeling an earthquake, according to the US Geological Survey . A former CNN editor in Vermont said glasses fell off her shelf.

How is that possible, considering it was just a mild 4.8 magnitude earthquake, not enough to cause any significant damage?

The rock formations that make up America's East Coast are considerably older than those on the West Coast — hundreds of millions of years older, according to the USGS . That makes them much denser.

Imagine putting your left hand down on a piece of slate and knocking on it with your right hand. You'd feel that. That's like how the East Coast is formed.

But now imagine putting your hand down on a pebble driveway and knocking — not so much. That's the West Coast. So even though earthquakes tend to be much stronger in the western part of the country, they're not felt nearly as far away as weaker quakes in the East.

Rail service is being slowed in the Northeast due to the earthquake

From CNN's Greg Wallace and Pete Muntea

Train service is being slowed after the 4.8 magnitude earthquake that rattled the Northeast this morning.

Amtrak said started inspecting its tracks shortly after 11 a.m. ET, and put speed restrictions in place throughout the region until those inspections were complete.

New Jersey Transit said there would be up to 20-minute delays in both directions due to bridge inspections after the quake.

Newark Light Rail service was suspended system-wide, according to NJ Transit. The River Line Light Rail service, meanwhile, was suspended in both directions between the Waterfront Entertainment Center and Trenton due to track inspections.

NOW: New York governor holds news briefing on earthquake

From CNN's Samantha Beech

New York Gov. Kathy Hochul is holding a news briefing at the State Capitol following this morning’s earthquake.

New York City Mayor Eric Adams and other city administration officials will hold a separate news briefing to discuss the impacts of the earthquake at 12 p.m. ET, according to his spokesperson.

New York governor says her team is assessing any impacts from quake

From CNN staff

New York Gov. Kathy Hochul said her team will be assessing any impact and any damage that may have resulted from the earthquake that struck New Jersey on Friday.

On X , Hochul said, “A 4.8 magnitude earthquake hit west of Manhattan and has been felt throughout New York. My team is assessing impacts and any damage that may have occurred, and we will update the public throughout the day.” and any damage that may have occurred, and we will update the public throughout the day.”

Hochul will hold a press briefing soon on the earthquake at the State Capitol, according to a notification from her office.

Philadelphia police aware of reports of seismic activity and urge people not to call 911 unless of emergency

From CNN’s Danny Freeman in Philadelphia

Philadelphia Police have asked people to only call 911 if they are reporting an emergency, following Friday's 4.8 magnitude earthquake in New Jersey.

Philadelphia Gov. Josh Shapiro added in a tweet that the earthquake was felt in parts of Pennsylvania.

"My team and @PEMAHQ are actively monitoring the situation and in contact with counties on any damage. We will keep Pennsylvanians updated," he said.

Biden has been briefed on earthquake, White House says

From CNN's Samantha Waldenberg

President Joe Biden has been briefed on Friday’s earthquake , according to White House press secretary Karine Jean-Pierre. 

Jean-Pierre  posted on social media  that the president is “in touch with his team who are monitoring potential impacts.” She added that the White House is in “touch with federal, state, and local officials as we learn more."

NYPD transit chief says no reports of structural damage to transit system following earthquake

There are no reports of damage to New York City's transit system following this morning's earthquake, New York City Police Department Chief of Transit Michael M. Kemper said.

Kemper said he has been briefed by his team regarding the earthquake felt across parts of the Northeast.

“There are no current reports of any structural damage and/or service disruptions to the NYC Transit system as a result,”  he said . “That said, our team is continuing to survey all lines & stations and we will keep you updated.”

No major incidents following earthquake, New York City Fire Department says

From CNN’s Nic F. Anderson in New York

The New York City Fire Department said there are no major incidents it is responding to at this time, in the aftermath of the New Jersey earthquake.

An FDNY spokesperson told CNN that around 10:30 a.m. ET, FDNY received reports of shaking buildings.

“We are responding to calls and evaluating structural stability. There are no major incidents at this time. We will continue to monitor," the spokesperson added.

Northeast earthquake is disrupting air travel

From CNN's Greg Wallace

A 4.8 magnitude earthquake in the Northeast is impacting air travel.  

The Federal Aviation Administration said flights to the New York Kennedy, Philadelphia, Baltimore, and Newark airports were being held.  

The air traffic control tower at Newark Liberty airport is being evacuated, a controller said in a radio transmission after the earthquake. That meant the flights were being held while controllers moved to an alternate location.  

"Nobody's going to go anywhere for the time being," a controller said over the radio frequency.  

The runways were in the process of being inspected for damage. Shortly after the earthquake, controllers at LaGuardia were still clearing flights for departure there.  

Federal Aviation Administration spokesperson Jeannie Shiffer calls the earthquake’s impact on air travel a “rapidly evolving situation.”

FAA will have to inspect runways at New York’s JFK and Newark airports before operations can resume.

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Your last-minute guide to Monday's total solar eclipse

A total solar eclipse will cross North America on Monday , offering millions a rare opportunity to see afternoon skies temporarily darken as the moon blocks the face of the sun.

Tune into NBC News NOW as Lester Holt hosts a two-hour special at 2 p.m. ET Monday from Indianapolis Motor Speedway.

The eclipse's path fortuitously cuts across Mexico, 15 U.S. states and a small part of eastern Canada. In all other states in the continental U.S., viewers will be treated to a partial solar eclipse, with the moon appearing to take a bite out of the sun and obscuring part of its light.

Here’s everything you need to know about the rare celestial event.

What is a solar eclipse?

Solar eclipses occur when the sun, moon and Earth align. The moon passes between Earth and sun, temporarily blocking the sun’s light and casting a shadow on Earth.

A total solar eclipse is when the moon fully obscures the sun, whereas a partial solar eclipse means it blocks just a portion of the sun’s face.

Solar eclipses occur only with the new moon. Because the moon’s orbit around Earth is tilted, the three bodies don’t always line up in a way that creates an eclipse.

“Imagine if the moon’s orbit were in the plane of Earth’s orbit around the sun — if that were the case, then every new moon, you’d have a total solar eclipse and every full moon, you’d have a lunar eclipse,” Neil DeGrasse Tyson, director of the Hayden Planetarium at the American Museum of Natural History, told NBC News. “So, because things don’t always align, it lends to the rarity of the event and the specialness of the event.”

Where and when will the eclipse be visible?

This year’s eclipse will follow a slightly wider path over more populated areas of the continental U.S. than other total solar eclipses have in the recent past.

NASA estimates that 31.6 million people live within what’s known as the path of totality, where the total solar eclipse will be visible. An additional 150 million people live within 200 miles of the path, according to the agency.

The path travels through Texas, Oklahoma, Arkansas, Missouri, Illinois, Kentucky, Indiana, Ohio, Pennsylvania, New York, Vermont, New Hampshire and Maine. Tiny parts of Michigan and Tennessee will also be able to witness totality if conditions are clear.

After the eclipse crosses into Canada, it will pass over southern Ontario, Quebec, New Brunswick, Prince Edward Island and Cape Breton, at the eastern end of Nova Scotia.

Those outside the path of totality can still take part in the astronomical event by viewing a partial solar eclipse — visible throughout all 48 states of the contiguous U.S. — or a NASA livestream.

The timing, including how long totality lasts, depends on the location, but some spots will see the moon fully cover the sun for up to 4 minutes and 28 seconds.

Below is a list of timings for some cities along the path of totality, as  provided by NASA . A number of other resources, including NationalEclipse.com  and  TimeandDate.com , can also help people plan.

• Dallas: Partial eclipse begins at 12:23 p.m. CT and totality at 1:40 p.m.
• Little Rock, Arkansas: Partial eclipse begins at 12:33 p.m. CT and totality at 1:51 p.m.
• Cleveland: Partial eclipse begins at 1:59 p.m. ET and totality at 3:13 p.m.
• Buffalo, New York: Partial eclipse begins at 2:04 p.m. ET and totality at 3:18 p.m.
• Lancaster, New Hampshire: Partial eclipse begins at 2:16 p.m. ET and totality at 3:27 p.m.

How to safely view a solar eclipse

It is never safe to gaze directly at the sun, even when it is partly or mostly covered by the moon. Special eclipse glasses or  pinhole projectors  are required to safely view solar eclipses and prevent eye damage. Failing to take the proper precautions can result in severe eye injury,  according to NASA .

Eclipse glasses are thousands of times darker than normal sunglasses and specially made to enable wearers to look at the sun during these kinds of celestial events.

Sky-watchers should also never view any part of the sun through binoculars, telescopes or camera lenses unless they have specific solar filters attached. Eclipse glasses should not be used with these devices, as they will not provide adequate protection.

However, during the few minutes of totality, when the moon is fully blocking the sun, it is safe to look with the naked eye.

Beware of fake eclipse glasses. On legitimate pairs, the lenses should have a silver appearance on the front and be black on the inside. The manufacturer’s name and address should be clearly labeled, and they should not be torn or punctured. Check, as well, for the ISO logo and the code “IS 12312-2” printed on the inside.

If you don’t have eclipse glasses, you can make a homemade pinhole projector, which lets sunlight in through a small hole, focuses it and projects it onto a piece of paper, wall or other surface to create an image of the sun that is safe to look at. 

All you need is two pieces of white cardboard or plain white paper, aluminum foil and a pin or thumbtack. Cut a 1- to 2-inch square or rectangle out of the center of a piece of white paper or cardboard. Tape aluminum foil over that cut-out shape, then use a pin or thumbtack to poke a tiny hole in the foil.

During the eclipse, place a second piece of white paper or cardboard on the ground as a screen and hold the projector with the foil facing up and your back to the sun. Adjusting how far you hold the projector from the second piece of paper will alter the size of the image on the makeshift screen.

What to look for while viewing the total solar eclipse

For people along the path of totality, there are some fun milestones to keep track of as the total solar eclipse unfolds.

As the eclipse progresses and the sun gets thinner in the sky, it will start to get eerily dark, according to Tyson.

When the last beams of sunlight are about to become obscured, look out for the “diamond ring effect”: The sun’s atmosphere will appear as an illuminated halo, and the last light still visible will look like the diamond of a giant ring.

As the sunlight decreases even further, an effect known as Baily’s beads will be created by the moon’s rugged terrain. Tiny “beads” of light will be visible for only a few seconds around the dark moon, as the last bits of sunlight peer through the moon’s mountains and valleys.

When the moon is fully blocking the sun, it is safe to remove eclipse glasses and look at the total solar eclipse with the naked eye.

Some lucky sky-watchers may even catch a glimpse of a comet .

Comet 12P/Pons-Brooks — nicknamed the “ devil comet ” because an eruption last year left it with two distinct trails of gas and ice in the shape of devil horns — is currently visible from the Northern Hemisphere as it swings through the inner solar system.

The comet can be seen in the early evenings by gazing toward the west-northwest horizon. During the eclipse, when skies darken during totality, it may be possible to see the comet near Jupiter, but its visibility will depend on whether it’s in the middle of an outburst and thus brighter than normal.

Most likely, all eyes will be on the alignment of the moon and sun.

“Most people won’t even notice,” Tyson said. “But if you know to look, it’s there.”

When is the next solar eclipse?

The next total solar eclipse will be in 2026, but it will mostly pass over the Arctic Ocean, with some visibility in Greenland, Iceland, Portugal and northern Spain. In 2027, a total solar eclipse will be visible in Spain and a swath of northern Africa.

The next total solar eclipse visible from North America will be in 2033, but only over Alaska. Then in 2044, a total solar eclipse will cross Montana, North Dakota, South Dakota, parts of Canada and Greenland.

The next total solar eclipse to cross the continental U.S. coast-to-coast in will occur in 2045. The path of totality for that eclipse will cut through California, Nevada, Utah, Colorado, New Mexico, Oklahoma, Kansas, Texas, Arkansas, Missouri, Mississippi, Louisiana, Alabama, Georgia and Florida.

Denise Chow is a reporter for NBC News Science focused on general science and climate change.

Lucas Thompson is a content producer for the NBC News Climate Unit.