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45 years ago: voyager 2 begins its epic journey to the outer planets and beyond, johnson space center.

Forty-five years ago, the Voyager 2 spacecraft left Earth to begin an epic journey that continues to this day. The first of a pair of spacecraft, Voyager 2 lifted off on Aug. 20, 1977. NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, manages the spacecraft on their missions to explore the outer planets and beyond. Taking advantage of a rare planetary alignment to use the gravity of one planet to redirect the spacecraft to the next, the Voyagers initially targeted only Jupiter and Saturn, but Voyager 2 went on to explore Uranus and Neptune as well. The Voyagers carried sophisticated instruments to conduct their in-depth explorations of the outer planets. Both spacecraft continue to return data as they make their way out of our solar system and enter interstellar space.

In the 1960s, mission designers at JPL noted that the next alignment of the outer planets that occurs only every 175 years would happen in the late 1970s. Technology had advanced sufficiently that spacecraft could take advantage of this rare alignment to flyby Jupiter and use its gravity to bend their trajectories to visit Saturn, and repeat the process to also visit Uranus, Neptune, and Pluto. Launching several missions to visit each planet individually would take much longer and cost much more. The original plan to send two pairs of Thermoelectric Outer Planet Spacecraft on these Grand Tours proved too costly leading to its cancellation in 1971. The next year, NASA approved a scaled-down version of the project to launch a pair of Mariner-class spacecraft in 1977 to explore just Jupiter and Saturn. On March 7, 1977, NASA Administrator James C. Fletcher announced the renaming of these Mariner Jupiter/Saturn 1977 spacecraft as Voyager 1 and 2. Scientists held out hope that one of them could ultimately visit Uranus and Neptune, thereby fulfilling most of the original Grand Tour’s objectives – Pluto would have to wait many more years for its first visit.

Each Voyager carried a suite of 11 instruments to study the planets during each encounter and to learn more about interplanetary space in the outer reaches of the solar system, including: 

• An imaging science system consisting of narrow-angle and wide-angle cameras to photograph the planet and its satellites.
• A radio science system to determine the planet’s physical properties.
• An infrared interferometer spectrometer to investigate local and global energy balance and atmospheric composition.
• An ultraviolet spectrometer to measure atmospheric properties.
• A magnetometer to analyze the planet’s magnetic field and interaction with the solar wind.
• A plasma spectrometer to investigate microscopic properties of plasma ions.
• A low energy charged particle device to measure fluxes and distributions of ions.
• A cosmic ray detection system to determine the origin and behavior of cosmic radiation.
• A planetary radio astronomy investigation to study radio emissions from Jupiter.
• A photopolarimeter to measure the planet’s surface composition.
• A plasma wave system to study the planet’s magnetosphere.

Voyager 2 left Earth first, lifting off on Aug. 20, 1977, atop a Titan IIIE-Centaur rocket from Launch Complex 41 at Cape Canaveral Air Force Station, now Cape Canaveral Space Force Station, in Florida. Although its twin launched two weeks later, it traveled on a faster trajectory and arrived at Jupiter four months earlier. Voyager 2 successfully crossed the asteroid belt between Dec. 10, 1977, and Oct. 21, 1978. In April 1978, its primary radio receiver failed, and it has been operating on its backup receiver ever since.

Voyager 2 conducted its observations of Jupiter between April 24 and Aug. 5, 1979, making its closest approach of 350,000 miles above the planet’s cloud tops on July 9. The spacecraft returned 17,000 images of Jupiter, many of its satellites, and confirmed Voyager 1’s discovery of a thin ring encircling the planet. Its other instruments returned information about Jupiter’s atmosphere and magnetic field. Jupiter’s massive gravity field bent the spacecraft’s trajectory, accelerating it toward Saturn. Voyager 2 began its long-range observations of the ringed planet on June 5, 1981, passed within 26,000 miles of the planet’s cloud tops on Aug. 26, and concluded its studies on Sept. 4. The spacecraft captured 16,000 photographs of the planet, its rings, and many of its known satellites. It discovered several new ones, while its instruments returned data about Saturn’s atmosphere. Saturn’s gravity sent Voyager 2 on to Uranus.

Voyager 2 carried out the first close-up observations of Uranus between Nov. 4, 1985, and Feb. 25, 1986, making its closest approach of 50,700 miles above the planet’s cloud tops on Jan. 24. It returned more than 7,000 photographs of the planet, its rings and moons, discovering two new rings and 11 new moons. The spacecraft’s instruments returned data about the planet’s atmosphere and its unusual magnetic field, tilted by 59 degrees compared to its rotational axis and offset from the planet’s center by about one-third of the planet’s radius. Voyager 2 took advantage of Uranus’ gravity to send it on to its last planetary destination, Neptune. The spacecraft conducted the first close-up observations of the eighth planet between June 5 and Oct. 2, 1989, making its flyby just 3,408 miles above its north pole on Aug. 25, its closest approach to any planet since leaving Earth in 1977. This trajectory allowed Voyager 2 to observe Neptune’s large moon Triton, the last solid object it explored. During the encounter, it returned more than 9,000 images of the planet, its atmosphere, dark rings, and moons, discovering six new moons. Like Uranus, Voyager 2’s instruments revealed that Neptune has an unusual magnetic field, not only tilted 47 degrees from the planet’s axis but also significantly offset from the planet’s center.

Following its reconnaissance of Neptune, Voyager 2 began its Interstellar Mission extension that continues to this day. Over the years, several of the spacecraft’s instruments have been turned off to conserve power, beginning with the imaging system in 1998, but it continues to return data about cosmic rays and the solar wind. On Nov. 5, 2018, six years after its twin, Voyager 2 crossed the heliopause, the boundary between the heliosphere – the bubble-like region of space created by the Sun – and the interstellar medium. Currently, Voyager 2 continues its mission, more than 12 billion miles from Earth, so distant that a signal from the spacecraft takes 18 hours to reach Earth, and just as long for a return signal to reach the craft. Engineers expect that Voyager 2 will continue to return data until about 2025. And just in case an alien intelligence finds it one day, Voyager 2 like its twin carries a gold-plated record that contains information about its home planet, including recordings of terrestrial sounds, music, and greetings in 55 languages. Engineers at NASA thoughtfully included Instructions on how to play the record.

For more on Voyagers 1 and 2, NASA’s longest-lived missions, please visit here , with thanks to our colleagues at JPL.

The voyage continues…

Voyager 2: An iconic spacecraft that's still exploring 45 years on

The interstellar vagabond continues to explore the cosmos along with its twin, Voyager 1.

Voyager 2 as the backup

Jupiter and saturn flyby, uranus and neptune flyby, voyager 2's interstellar adventure, voyager 2's legacy, additional information.

Voyager 2, was the first of two twin probes NASA sent to investigate the outer planets of our solar system. 

The probe was launched aboard a Titan IIIE-Centaur from Cape Canaveral Space Launch Complex 41 (previously Launch Complex 41) on Aug. 20, 1977, its twin spacecraft Voyager 1 was launched about two weeks later on Sept. 5. NASA planned for the Voyager spacecraft to take advantage of an alignment of the outer planets that takes place only every 176 years. The alignment would allow both probes to swing from one planet to the next, with a gravity boost to help them along the way.

While Voyager 1 focused on Jupiter and Saturn , Voyager 2 visited both those planets and also ventured to Uranus and Neptune. Voyager 2's mission to those last two planets would be humanity's only visit in the 20th century.

Related: Celebrate 45 years of Voyager with these amazing images of our solar system (gallery)

Voyager 2 is now traveling through interstellar space. As of early November 2018, NASA announced that Voyager 2 had crossed the outer edge of our solar system ( Voyager 1 crossed the boundary into interstellar space in 2012. ) Voyager 2 is now approximately 12 billion miles (19 billion kilometers) away from Earth and counting!  

Although there was not enough money in Voyager 2's budget to guarantee it would still work when flying past Uranus and Neptune, its trajectory was designed to go past those planets anyway. If the spacecraft were still working after Saturn, NASA could try to take pictures of the other planets.

Voyager 2 was ready as a backup for Voyager 1. If Voyager 1 failed when taking pictures of Jupiter and Saturn, NASA was prepared to alter Voyager 2's path to follow Voyager 1's trajectory. It would cut off the Uranus and Neptune option, but still, preserve the possibility of capturing images.

The backup plan was never executed, though, because Voyager 1 went on to make many discoveries at Jupiter and Saturn, working well enough for NASA to carry out its original plans for Voyager 2.

Voyager 2 reached Jupiter in 1979, two years after launching from Cape Canaveral. Since Voyager 1 had just gone through the system four months earlier, Voyager 2's arrival allowed NASA to take valuable comparison shots of Jupiter and its moons. It captured changes in the Great Red Spot and also resolved some of the moon's surfaces in greater detail.

Voyager 2 took pictures of many of Jupiter's satellites. Among its most spectacular findings were pictures from the icy moon Europa . Voyager 2 snapped detailed photos of the icy moon's cracks from 128,000 miles (205,996 km) away and revealed no change in elevation anywhere on the moon's surface.

Proving that moons are abundant around the outer planets, Voyager 2 happened to image Adrastea, a small moon of Jupiter, only months after Voyager 1 found two other Jupiter moons, Thebe and Metis. Adrastea is exceptionally small, only about 19 miles (30.5 kilometers) in diameter at the smallest estimate.

Next in line was Saturn. Voyager 2  became the third spacecraft to visit Saturn when it arrived at its closest point to the ringed planet on Aug. 26, 1981, and took hundreds of pictures of the planet, its moons and its rings . Suspecting that Saturn might be circled by many ringlets, scientists conducted an experiment. They watched the star Delta Scorpii for nearly two and a half hours as it passed through the plane of the rings. As expected, the star's flickering light revealed ringlets as small as 330 feet (100 meters) in diameter. 

Voyager 2's made its closest approach to Uranus on Jan. 24, 1986, becoming the first spacecraft to visit the ice giant. The probe made several observations of the planet, noting that the south pole was facing the sun and that its atmosphere is about 85% hydrogen and 15% helium. 

Additionally, Voyager 2 discovered rings around Uranus, 10 new moons and a magnetic field that, oddly, was 55 degrees off the planet's axis. Astronomers are still puzzling over Uranus' orientation today.

Voyager 2's pictures of the moon Miranda revealed it to be perhaps the strangest moon in the solar system. Its jumbled-up surface appears as though it was pushed together and broken apart several times.

The spacecraft then made it to Neptune , reaching the closest point on Aug. 25, 1989. It skimmed about 3,000 miles from the top of the planet's atmosphere and spotted five new moons as well as four rings around the planet. Remarkably, Voyager 2 is currently the only human-made object to have flown by the intriguing ice giant, according to NASA .

On November 5, 2018, Voyager 2 crossed the heliopause — the boundary between the heliosphere and interstellar space. At this stage, the probe was 119 astronomical units from the sun. (One AU is the average Earth-sun distance, which is about 93 million miles, or 150 million kilometers.) Voyager 1 made the crossing at nearly the same distance, 121.6 AU.

According to NASA Jet Propulsion Laboratory (JPL) , Voyager 2 has enough fuel to keep its instruments running until at least 2025. By then, the spacecraft will be approximately 11.4 billion miles (18.4 billion kilometers) away from the sun. 

But Voyager 2 is destined to roam the Milky Way long after its instruments have stopped working.

In about 40,000 years Voyager 2 will pass 1.7 light-years (9.7 trillion miles) from the star Ross 248, according to NASA JPL. The cosmic vagabond will continue its journey through interstellar space and pass 4.3 light-years, (25 trillion miles) from Sirius in about 296,000 years. 

Voyager 2's observations paved the way for later missions. The Cassini spacecraft, which was at Saturn between 2004 and 2017, tracked down evidence of liquid water at the planet's icy moons several decades after the Voyagers initially revealed the possible presence of water. Cassini also mapped the moon, Titan , after the Voyagers took pictures of its thick atmosphere.

Voyager 2's images of Uranus and Neptune also serve as a baseline for current observations of those giant planets. In 2014, astronomers were surprised to see giant storms on Uranus — a big change from when Voyager 2 flew by the planet in 1986. 

To see where Voyager 2 is now you can check out the mission status with resources from NASA . Learn more about the iconic spacecraft with the National Air and Space Museum .  

Bibliography

NASA. In depth: Voyager 2. NASA. Retrieved August 17, 2022, from www.solarsystem.nasa.gov/missions/voyager-2/in-depth/

NASA. Voyager - mission status. NASA. Retrieved August 17, 2022, from www.voyager.jpl.nasa.gov/mission/status/

NASA. Voyager - the interstellar mission. NASA. Retrieved August 17, 2022, from www. voyager.jpl.nasa.gov/mission/interstellar-mission

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Elizabeth Howell (she/her), Ph.D., is a staff writer in the spaceflight channel since 2022 covering diversity, education and gaming as well. She was contributing writer for Space.com for 10 years before joining full-time. Elizabeth's reporting includes multiple exclusives with the White House and Office of the Vice-President of the United States, an exclusive conversation with aspiring space tourist (and NSYNC bassist) Lance Bass, speaking several times with the International Space Station, witnessing five human spaceflight launches on two continents, flying parabolic, working inside a spacesuit, and participating in a simulated Mars mission. Her latest book, " Why Am I Taller ?", is co-written with astronaut Dave Williams. Elizabeth holds a Ph.D. and M.Sc. in Space Studies from the University of North Dakota, a Bachelor of Journalism from Canada's Carleton University and a Bachelor of History from Canada's Athabasca University. Elizabeth is also a post-secondary instructor in communications and science at several institutions since 2015; her experience includes developing and teaching an astronomy course at Canada's Algonquin College (with Indigenous content as well) to more than 1,000 students since 2020. Elizabeth first got interested in space after watching the movie Apollo 13 in 1996, and still wants to be an astronaut someday. Mastodon: https://qoto.org/@howellspace

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The Voyager missions

Highlights Voyager 1 and Voyager 2 launched in 1977 and made a grand tour of the solar system's outer planets. They are the only functioning spacecraft in interstellar space, and they are still sending back measurements of the interstellar medium. Each spacecraft carries a copy of the golden record, a missive from Earth to any alien lifeforms that may find the probes in the future.

What are the Voyager missions?

The Voyager program consists of two spacecraft: Voyager 1 and Voyager 2. Voyager 2 was actually launched first, in August 1977, but Voyager 1 was sent on a faster trajectory when it launched about two weeks later. They are the only two functioning spacecraft currently in interstellar space, beyond the environment controlled by the sun.

Voyager 2’s path took it past Jupiter in 1979, Saturn in 1981, Uranus in 1985, and Neptune in 1989. It is the only spacecraft to have visited Uranus or Neptune, and has provided much of the information that we use to characterize them now.

Because of its higher speed and more direct trajectory, Voyager 1 overtook Voyager 2 just a few months after they launched. It visited Jupiter in 1979 and Saturn in 1980. It overtook Pioneer 10 — the only other spacecraft in interstellar space thus far — in 1998 and is now the most distant artificial object from Earth.

How the Voyagers work

The two spacecraft are identical, each with a radio dish 3.7 meters (12 feet) across to transmit data back to Earth and a set of 16 thrusters to control their orientations and point their dishes toward Earth. The thrusters run on hydrazine fuel, but the electronic components of each spacecraft are powered by thermoelectric generators that run on plutonium. Each carries 11 scientific instruments, about half of which were designed just for observing planets and have now been shut off. The instruments that are now off include several cameras and spectrometers to examine the planets, as well as two radio-based experiments. Voyager 2 now has five functioning instruments: a magnetometer, a spectrometer designed to investigate plasmas, an instrument to measure low-energy charged particles and one for cosmic rays, and one that measures plasma waves. Voyager 1 only has four of those, as its plasma spectrometer is broken.

Jupiter findings

Over the course of their grand tours of the solar system, the Voyagers took tens of thousands of images and measurements that significantly changed our understanding of the outer planets.

At Jupiter, they gave us our first detailed ideas of how the planet’s atmosphere moves and evolves, showing that the Great Red Spot was a counter-clockwise rotating storm that interacted with other, smaller storms. They were also the first missions to spot a faint, dusty ring around Jupiter. Finally, they observed some of Jupiter’s moons, discovering Io’s volcanism, finding the linear features on Europa that were among the first hints that it might have an ocean beneath its surface, and granting Ganymede the title of largest moon in the solar system, a superlative that was previously thought to belong to Saturn’s moon Titan.

Saturn findings

Next, each spacecraft flew past Saturn, where they measured the composition and structure of Saturn’s atmosphere , and Voyager 1 also peered into Titan’s thick haze. Its observations led to the idea that Titan might have liquid hydrocarbons on its surface, a hypothesis that has since been verified by other missions. When the two missions observed Saturn’s rings, they found the gaps and waves that are well-known today. Voyager 1 also spotted three previously-unknown moons orbiting Saturn: Atlas, Prometheus, and Pandora.

Uranus and Neptune findings

After this, Voyager 1 headed out of the solar system, while Voyager 2 headed toward Uranus . There, it found 11 previously-unknown moons and two previously-unknown rings. Many of the phenomena it observed on Uranus remained unexplained, such as its unusual magnetic field and an unexpected lack of major temperature changes at different latitudes.

Voyager 2’s final stop, 12 years after it left Earth, was Neptune. When it arrived , it continued its streak of finding new moons with another haul of 6 small satellites, as well as finding rings around Neptune. As it did at Uranus, it observed the planet’s composition and magnetic field. It also found volcanic vents on Neptune’s huge moon Triton before it joined Voyager 1 on the way to interstellar space.

Interstellar space

Interstellar space begins at the heliopause, where the solar wind – a flow of charged particles released by the sun – is too weak to continue pushing against the interstellar medium, and the pressure from the two balances out. Voyager 1 officially entered interstellar space in August 2012, and Voyager 2 joined it  in November 2018.

These exits were instrumental in enabling astronomers to determine where exactly the edge of interstellar space is, something that’s difficult to measure from within the solar system. They showed that interstellar space begins just over 18 billion kilometers (about 11 billion miles) from the sun. The spacecraft continue to send back data on the structure of the interstellar medium.

After its planetary encounters, Voyager 1 took the iconic “Pale Blue Dot” image , showing Earth from about 6 billion kilometers (3.7 billion miles) away. As of 2021 , Voyager 1 is about 155 astronomical units (14.4 billion miles) from Earth, and Voyager 2 is nearly 129 astronomical units (12 billion miles) away.

The golden records

Each Voyager spacecraft has a golden phonograph record affixed to its side, intended as time capsules from Earth to any extraterrestrial life that might find the probes sometime in the distant future. They are inscribed with a message from Jimmy Carter, the U.S. President at the time of launch, which reads: “This is a present from a small, distant world, a token of our sounds, our science, our images, our music, our thoughts and our feelings. We are attempting to survive our time so we may live into yours.”

The covers of the records have several images inscribed, including visual instructions on how to play them, a map of our solar system’s location with respect to a set of 14 pulsars, and a drawing of a hydrogen atom. They are plated with uranium – its rate of decay will allow any future discoverers of either of the records to calculate when they were created.

The records’ contents were selected by a committee chaired by Carl Sagan. Each contains 115 images, including scientific diagrams of the solar system and its planets, the flora and fauna of Earth, and examples of human culture. There are natural sounds, including breaking surf and birdsong, spoken greetings in 55 languages, an hour of brainwave recordings, and an eclectic selection of music ranging from Beethoven to Chuck Berry to a variety of folk music.

Learn more Voyager Mission Status Bulletin Archives Experience A Message From Earth - Inspired by the Voyager Golden Record Neptune, planet of wind and ice

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Teachable Moments | December 18, 2018

Then there were two: voyager 2 reaches interstellar space.

By Ota Lutz

In the News

The Voyager 2 spacecraft, launched in 1977, has reached interstellar space , a region beyond the heliosphere – the protective bubble of particles and magnetic fields created by the Sun – where the only other human-made object is its twin, Voyager 1.

The achievement means new opportunities for scientists to study this mysterious region. And for educators, it’s a chance to get students exploring the scale and anatomy of our solar system, plus the engineering and math required for such an epic journey.

How They Did It

Launched just 16 days apart, Voyager 1 and Voyager 2 were designed to take advantage of a rare alignment of the outer planets that only occurs once every 176 years. Their trajectory took them by the outer planets, where they captured never-before-seen images. They were also able to steal a little momentum from Jupiter and Saturn that helped send them on a path toward interstellar space. This “ gravity assist ” gave the spacecraft a velocity boost without expending any fuel. Though both spacecraft were destined for interstellar space, they followed slightly different trajectories.

An illustration of the trajectories of Voyager 1 and Voyager 2. Image credit: NASA/JPL-Caltech | + Expand image

Voyager 1 followed a path that enabled it to fly by Jupiter in 1979, discovering the gas giant’s rings. It continued on for a 1980 close encounter with Saturn’s moon Titan before a gravity assist from Saturn hurled it above the plane of the solar system and out toward interstellar space. After Voyager 2 visited Jupiter in 1979 and Saturn in 1981, it continued on to encounter Uranus in 1986, where it obtained another assist. Its last planetary visit before heading out of the solar system was Neptune in 1989, where the gas giant’s gravity sent the probe in a southward direction toward interstellar space. Since the end of its prime mission at Neptune, Voyager 2 has been using its onboard instruments to continue sensing the environment around it, communicating data back to scientists on Earth. It was this data that scientists used to determine Voyager 2 had entered interstellar space.

How We Know

Interstellar space, the region between the stars, is beyond the influence of the solar wind, charged particles emanating from the Sun, and before the influence of the stellar wind of another star. One hint that Voyager 2 was nearing interstellar space came in late August when the Cosmic Ray Subsystem, an instrument that measures cosmic rays coming from the Sun and galactic cosmic rays coming from outside our solar system, measured an increase in galactic cosmic rays hitting the spacecraft. Then on November 5, the instrument detected a sharp decrease in high energy particles from the Sun. That downward trend continued over the following weeks.

The data from the cosmic ray instrument provided strong evidence that Voyager 2 had entered interstellar space because its twin had returned similar data when it crossed the boundary of the heliosheath . But the most compelling evidence came from its Plasma Science Experiment – an instrument that had stopped working on Voyager 1 in 1980. Until recently, the space surrounding Voyager 2 was filled mostly with plasma flowing out from our Sun. This outflow, called the solar wind, creates a bubble, the heliosphere, that envelopes all the planets in our solar system. Voyager 2’s Plasma Science Experiment can detect the speed, density, temperature, pressure and flux of that solar wind. On the same day that the spacecraft’s cosmic ray instrument detected a steep decline in the number of solar energetic particles, the plasma science instrument observed a decline in the speed of the solar wind. Since that date, the plasma instrument has observed no solar wind flow in the environment around Voyager 2, which makes mission scientists confident the probe has entered interstellar space.

Though the spacecraft have left the heliosphere, Voyager 1 and Voyager 2 have not yet left the solar system, and won't be leaving anytime soon. The boundary of the solar system is considered to be beyond the outer edge of the Oort Cloud , a collection of small objects that are still under the influence of the Sun's gravity. The width of the Oort Cloud is not known precisely, but it is estimated to begin at about 1,000 astronomical units from the Sun and extend to about 100,000 AU. (One astronomical unit, or AU, is the distance from the Sun to Earth.) It will take about 300 years for Voyager 2 to reach the inner edge of the Oort Cloud and possibly 30,000 years to fly beyond it. By that time, both Voyager spacecraft will be completely out of the hydrazine fuel used to point them toward Earth (to send and receive data) and their power sources will have decayed beyond their usable lifetime.

Why It’s Important

Since the Voyager spacecraft launched more than 40 years ago, no other NASA missions have encountered as many planets (some of which had never been visited) and continued making science observations from such great distances. Other spacecraft, such as New Horizons and Pioneer 10 and 11, will eventually make it to interstellar space, but we will have no data from them to confirm their arrival or explore the region because their instruments already have or will have shut off by then.

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Interstellar space is a region that’s still mysterious because until 2012, when Voyager 1 arrived there , no spacecraft had visited it. Now, data from Voyager 2 will help add to scientists’ growing understanding of the region. Scientists are hoping to continue using Voyager 2’s plasma science instrument to study the properties of the ionized gases, or plasma, that exist in the interstellar medium by making direct measurements of the plasma density and temperature. This new data may shed more light on the evolution of our solar neighborhood and will most certainly provide a window into the exciting unexplored region of interstellar space, improving our understanding of space and our place in it.

As power wanes on Voyager 2, scientists will have to make tough choices about which instruments to keep turned on. Further complicating the situation is the freezing cold temperature at which the spacecraft is currently operating – perilously close to the freezing point of its hydrazine fuel. But for as long as both Voyager spacecraft are able to maintain power and communication, we will continue to learn about the uncharted territory of interstellar space.

Use these standards-aligned lessons and related activities to get students doing math and science with a real-world (and space!) connection.

Solar System Bead Activity

Students create a scale model of the solar system using beads and string.

Time 30 mins - 1 hr

Catching a Whisper from Space

Students kinesthetically model the mathematics of how NASA communicates with spacecraft.

Grades 4-12

Time 1-2 hrs

Solar System Scroll

Students predict the scale of our solar system and the distance between planets, then check their answers using fractions.

Time < 30 mins

*NEW* Modeling the Structure of the Solar System

Students will learn about the structure of the solar system and be able to identify analogous regions in a dynamic, 2-D kitchen-sink model.

Grades 6-12

Hear Here: A 'Pi in the Sky' Math Challenge

Students use the mathematical constant pi to determine what fraction of a signal from Voyager 1 – the most distant spacecraft – reaches Earth.

Grades 10-12

Explore More

• News Release: “ NASA’s Voyager 2 Probe Enters Interstellar Space ” – Dec. 10, 2018
• News Release: “ NASA Spacecraft Embarks on Historic Journey Into Interstellar Space ” – September 12, 2013
• Voyager Mission
• Voyager Images
• Voyager 2: Interstellar, by the Numbers
• Commemorative Voyager Posters

TAGS: Teachers , Educators , Science , Engineering , Technology , Solar System , Voyager , Spacecraft , Educator Resources , Lessons , Activities

Ota Lutz , K-12 Education Group Manager, NASA-JPL Education Office

Ota Lutz is the manager of the K-12 Education Group at NASA’s Jet Propulsion Laboratory. When she’s not writing new lessons or teaching, she’s probably cooking something delicious, volunteering in the community, or dreaming about where she will travel next.

• Object Information
• Planetarium

Voyager 2 live position and data

This page shows Voyager 2 location and other relevant astronomical data in real time. The celestial coordinates, magnitude, distances and speed are updated in real time and are computed using high quality data sets provided by the JPL Horizons ephemeris service (see acknowledgements for details). The sky map shown in the background represents a rectangular portion of the sky 60x40 arcminutes wide. By comparison the diameter of the full Moon is about 30 arcmins, so the full horizontal extent of the map is approximately 2 full Moons wide. Depending on the device you are using, the map can be dragged horizondally or vertically using the mouse or touchscreen. The deep sky image in the background is provided by the Digitized Sky Survey ( acknowledgements ).

Current close conjunctions

List of bright objects (stars brighter than magnitude 9.0 and galaxies brighter than magmitude 14.0) close to Voyager 2 (less than 1.5 degrees):

Additional resources

• 15 Days Ephemerides
• Interactive Sky Map (Planetarium)
• Rise & Set Times
• Distance from Earth

Astronomy databases

• The Digitized Sky Survey, a photographic survey of the whole sky created using images from different telescopes, including the Oschin Schmidt Telescope on Palomar Mountain
• The Hipparcos Star Catalogue, containing more than 100.000 bright stars
• The PGC 2003 Catalogue, containing information about 1 million galaxies
• The GSC 2.3 Catalogue, containing information about more than 2 billion stars and galaxies

• The Contents
• The Making of
• Where Are They Now
• Frequently Asked Questions
• Q & A with Ed Stone

golden record

Where are they now.

• frequently asked questions
• Q&A with Ed Stone

Galleries of Images Voyager Took

The Voyager 1 and 2 spacecraft explored Jupiter, Saturn, Uranus and Neptune before starting their journey toward interstellar space. Here you'll find some of those iconic images, including "The Pale Blue Dot" - famously described by Carl Sagan - and what are still the only up-close images of Uranus and Neptune.

Photography of Jupiter began in January 1979, when images of the brightly banded planet already exceeded the best taken from Earth. Voyager 1 completed its Jupiter encounter in early April, after taking almost 19,000 pictures and many other scientific measurements. Voyager 2 picked up the baton in late April and its encounter continued into August. They took more than 33,000 pictures of Jupiter and its five major satellites.

The Voyager 1 and 2 Saturn encounters occurred nine months apart, in November 1980 and August 1981. Voyager 1 is leaving the solar system. Voyager 2 completed its encounter with Uranus in January 1986 and with Neptune in August 1989, and is now also en route out of the solar system.

NASA's Voyager 2 spacecraft flew closely past distant Uranus, the seventh planet from the Sun, in January. At its closet, the spacecraft came within 81,800 kilometers (50,600 miles) of Uranus's cloudtops on Jan. 24, 1986. Voyager 2 radioed thousands of images and voluminous amounts of other scientific data on the planet, its moons, rings, atmosphere, interior and the magnetic environment surrounding Uranus.

In the summer of 1989, NASA's Voyager 2 became the first spacecraft to observe the planet Neptune, its final planetary target. Passing about 4,950 kilometers (3,000 miles) above Neptune's north pole, Voyager 2 made its closest approach to any planet since leaving Earth 12 years ago. Five hours later, Voyager 2 passed about 40,000 kilometers (25,000 miles) from Neptune's largest moon, Triton, the last solid body the spacecraft will have an opportunity to study.

This narrow-angle color image of the Earth, dubbed 'Pale Blue Dot', is a part of the first ever 'portrait' of the solar system taken by Voyager 1. The spacecraft acquired a total of 60 frames for a mosaic of the solar system from a distance of more than 4 billion miles from Earth and about 32 degrees above the ecliptic. From Voyager's great distance Earth is a mere point of light, less than the size of a picture element even in the narrow-angle camera. Earth was a crescent only 0.12 pixel in size. Coincidentally, Earth lies right in the center of one of the scattered light rays resulting from taking the image so close to the sun. This blown-up image of the Earth was taken through three color filters -- violet, blue and green -- and recombined to produce the color image. The background features in the image are artifacts resulting from the magnification.

Voyager 2 Trajectory through the Solar System

This visualization tracks the trajectory of the Voyager 2 spacecraft through the solar system. Launched on August 20, 1977, it was one of two spacecraft sent to visit the giant planets of the outer solar system.

Like Voyager 1, Voyager 2 flew by Jupiter and Saturn, but the Voyager 2 mission was extended to fly by Uranus and Neptune before being directed out of the solar system.

To fit the 40-year history of the mission into a short visualization, the pacing of time accelerates through most of the movie, starting at about 5 days per second at the beginning and speeding up to about 11 months per second after the planet flybys are passed.

The termination shock and heliopause are the 'boundaries' created when the plasma between the stars interacts with the plasma flowing outward from the Sun. They are represented with simple grid models and oriented so their 'nose' is pointed in the direction (Right Ascension = 17h 24m, declination = 17 degrees south) represented by more recent measurements from other missions.