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How fast are the Voyager spacecrafts travelling?

NASA's Voyage probes are speeding their way around the Solar System.

Keiron Allen

Asked by: Anonymous

Launched in 1977, NASA’s two Voyager probes surveyed Jupiter and Saturn, with Voyager 2 also visiting Uranus and Neptune before heading out of the Solar System. Voyager 1 has since become the fastest and most distant man-made object in the Universe, travelling at around 61,500km/h at a distance of 17.6 billion km from the Earth. Perhaps most incredible of all, NASA is still in communication with it, despite radio signals taking 16 hours to reach it.

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Plasma data measured by Voyager 2 up through 28 March 2024 (2024/088)

The outer atmosphere of the sun expands outward to form the solar wind, with average speeds of 400 km/sec (roughly one million miles per hour). the plasma science experiment on voyager 2 measures that speed every 192 seconds, and that information is returned to earth over the deep space net., voyager 2 currents (near and beyond the heliopause), the currents in the lowest l-mode channel of the pls d cup. the d cup points nearest to the interstellar plasma flow direction. the d1 cup covers the energy range 10-30 ev. at 2018.86 voyager 2 crossed the heliopause. v2 is making the first measurements of the interstellar plasma. we removed noisy and otherwise contaminated data from this plot., voyager 2 solar wind speed plots (up thru the heliopause), - click on figure to see larger version of each plot, these plots show hourly averages of the solar wind speeds measured by voyager 2 over the last 3800 and 100 days, prior to the heliopause, respectively., acquiring the voyager 1 and 2 data, voyager plasma data are available from mit through the links below (but note that updated versions of some browsers no longer support ftp links) or directly through anonymous ftp to space.mit.edu. (cd pub/plasma/vgr). please look at the readme files in each directory before using these data., voyager 1: hourly averages and fine resolution data are available by year for 1977-1980., voyager 2: daily averages , hourly averages and fine resolution data are available by year for 1977-heliopause (november, 2018). in addition, currents (l-modes) and (m-modes) are available (2018-present)., show recent events., voyager 2 solar wind dynamic pressure (up thru the heliopause), these plots show hourly averages of the solar wind dynamic pressure observed by voyager 2 over the entire mission (100-day averages) and over the last ten years (25-day averages), respectively. these pressures are normalized to 1 au by multiplying by the square of the spacecraft's distance., voyager data overview (up thru the heliopause), these plots show 50-day averages of the solar wind speed, density, and temperature over the life of the voyager mission (from 1977 to the heliopause), and 1-day averages over the last three years prior to the heliopause, respectively. the density shown is normalized to earth by multiplying by the distance to voyager in au squared., nasa jpl voyager project home page, for more information contact john richardson at mit (e-mail: [email protected])..

We Finally Know What Happened When Voyager 2 Reached Interstellar Space

A few big takeaways from the craft's incredible journey.

• The spacecraft reached the interstellar boundary between our solar system and interstellar space in 2018. Voyager 1 reached the boundary in 2012.
• Both spacecraft were launched in 1977, and have far surpassed scientists' expectations.

Scientists have finally analyzed data from Voyager 2’s journey to interstellar space and discovered a number of surprising differences—plus a few strange similarities.

Voyager 1 and 2 launched in August and October of 1977, respectively, and set out to explore the far reaches of the solar system and beyond. The spacecraft have revealed a vast amount of insight into distant planets and snapped pictures of previously undiscovered moons. Still, more than 40 years after their launch, they continue to provide scientists with an unparalleled look at the universe.

In 2012, Voyager 1 became the first spacecraft to reach interstellar space. Last year, Voyager 2 joined its companion in the interstellar medium, reaching the boundary set 119 times the Earth–sun distance away from Earth. The transition from our solar system to interstellar space, the researchers say, may take less than a day to cross. The data from Voyager 2’s crossing was published November 4 in a series of five papers in Nature Astronomy .

The heliopause is the theoretical boundary at which the sun’s solar wind meets interstellar winds, which are shot out from supernovae that have exploded millions of years ago. Additionally, galactic cosmic rays try to flow into our solar system, but only 30 percent of these rays actually reach Earth. Voyager 1 and 2 were also able to study changes in the magnetic fields within and outside of our solar system.

The two spacecraft reached interstellar space during different periods of solar activity, meaning conditions along the boundary were markedly different. Voyager 1 reached the interstellar boundary during the sun’s solar minimum, whereas Voyager 2 reached the boundary during the solar maximum, a period of heightened activity. Additionally, unlike its quicker counterpart, Voyager 2’s mission has largely taken place in Earth’s southern hemisphere.

The researchers also discovered that solar material was “leaking” out into the interstellar medium. “That was very different than what happened with Voyager 1, where hardly any material was leaking out,” said Tom Krimigis of John’s Hopkins’s Applied Physics Laboratory in an October 31 press conference.

In the case of Voyager 1, the team saw the opposite, where interstellar particles leaked into our solar system. The team hopes to reconvene to take a closer look at their data in the near future to understand how and why these particles slip out of the grasp of our solar system.

Another perplexing discovery? The direction of the magnetic fields both inside and outside of the heliopause is aligned, as was the case with Voyager 1. Leonard Burlaga of NASA Goddard Space Flight Center said scientists can dismiss the alignment of the magnetic fields once, but twice would be a remarkable coincidence. The strength of the magnetic field was stronger in interstellar space, the Voyager 2 found.

The scientists also discovered that the heliopause itself is much thinner and smoother than expected, and that the interstellar medium tucked close to the boundary layer, where solar and interstellar winds meet, is much hotter and unpredictable than expected. This newest research also revealed that the boundary layer itself may be more complex than initially thought, with multiple layers of different temperature, density, and speed.

Voyager 1 and 2 have roughly five years before they'll lose the use of their scientific instruments, said Ed Stone of the California Institute of Technology during the press conference. "When the two voyagers were launched, the space age was only 20 years old, Stone said. "So it was hard to know at that time that anything could last over 40 years."

There's still a lot left to explore, and the data dump has sparked a desire to explore faster, farther, and deeper into interstellar space.

Jennifer Leman is a science journalist and senior features editor at Popular Mechanics, Runner's World, and Bicycling. A graduate of the Science Communication Program at UC Santa Cruz, her work has appeared in The Atlantic, Scientific American, Science News and Nature. Her favorite stories illuminate Earth's many wonders and hazards.

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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.

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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An illustration shows the position of NASA's Voyager 1 and Voyager 2 probes outside of the heliosphere, a protective bubble created by the sun that extends well past the orbit of Pluto.

Interstellar space even weirder than expected, NASA probe reveals

The spacecraft is just the second ever to venture beyond the boundary that separates us from the rest of the galaxy.

In the blackness of space billions of miles from home, NASA’s Voyager 2 marked a milestone of exploration, becoming just the second spacecraft ever to enter interstellar space in November 2018. Now, a day before the anniversary of that celestial exit, scientists have revealed what Voyager 2 saw as it crossed the threshold—and it’s giving humans new insight into some of the big mysteries of our solar system.

The findings, spread across five studies published today in Nature Astronomy , mark the first time that a spacecraft has directly sampled the electrically charged hazes, or plasmas, that fill both interstellar space and the solar system’s farthest outskirts. It’s another first for the spacecraft, which was launched in 1977 and performed the first—and only—flybys of the ice giant planets Uranus and Neptune. ( Find out more about the Voyager probes’ “grand tour”—and why it almost didn’t happen .)

See pictures from Voyager 2's solar system tour

Voyager 2’s charge into interstellar space follows that of sibling Voyager 1, which accomplished the same feat in 2012. The two spacecrafts’ data have many features in common, such as the overall density of the particles they’ve encountered in interstellar space. But intriguingly, the twin craft also saw some key differences on their way out—raising new questions about our sun’s movement through the galaxy.

“This has really been a wonderful journey,” Voyager project scientist Ed Stone , a physicist at Caltech, said in a press briefing last week.

“It’s just really exciting that humankind is interstellar,” adds physicist Jamie Rankin , a postdoctoral researcher at Princeton University who wasn’t involved with the studies. “We have been interstellar travelers since Voyager 1 crossed, but now, Voyager 2’s cross is even more exciting, because we can now compare two very different locations ... in the interstellar medium.”

Inside the bubble

To make sense of Voyager 2’s latest findings, it helps to know that the sun isn’t a quietly burning ball of light. Our star is a raging nuclear furnace hurtling through the galaxy at about 450,000 miles an hour as it orbits the galactic center.

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The sun is also rent through with twisted, braided magnetic fields and, as a result, its surface constantly throws off a breeze of electrically charged particles called the solar wind. This gust rushes out in all directions, carrying the sun’s magnetic field with it. Eventually, the solar wind smashes into the interstellar medium, the debris from ancient stellar explosions that lurks in the spaces between stars.

Like oil and water, the solar wind and the interstellar medium don’t perfectly mix, so the solar wind forms a bubble within the interstellar medium called the heliosphere. Based on Voyager data, this bubble extends about 11 billion miles from the sun at its leading edge, surrounding the sun, all eight planets, and much of the outer objects orbiting our star. Good thing, too: The protective heliosphere shields everything inside it, including our fragile DNA, from most of the galaxy’s highest-energy radiation.

The heliosphere’s outermost edge, called the heliopause, marks the start of interstellar space. Understanding this threshold has implications for our picture of the sun’s journey through the galaxy, which in turn can tell us more about the situations of other stars scattered across the cosmos.

“We are trying to understand the nature of that boundary, where these two winds collide and mix,” Stone said during the briefing. “How do they mix, and how much spillage is there from inside to outside the bubble, and from outside the bubble to inside?”

Scientists got their first good look at the heliopause on August 25, 2012, when Voyager 1 first entered interstellar space. What they began to see left them scratching their heads. For instance, researchers now know that the interstellar magnetic field is about two to three times stronger than expected, which means, in turn, that interstellar particles exert up to ten times as much pressure on our heliosphere than previously thought.

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“It is our first platform to actually experience the interstellar medium, so it is quite literally a pathfinder for us,” says heliophysicist Patrick Koehn , a program scientist at NASA headquarters.

Leaky boundary

But for all that Voyager 1 upended expectations, its revelations were incomplete. Back in 1980, its instrument that measured the temperature of plasmas stopped working. Voyager 2’s plasma instrument is still working just fine, though, so when it crossed the heliopause on November 5, 2018, scientists could get a much better look at this border.

For the first time, researchers could see that as an object gets within 140 million miles of the heliopause, the plasma surrounding it slows, heats up, and gets more dense. And on the other side of the boundary, the interstellar medium is at least 54,000 degrees Fahrenheit, which is hotter than expected. However, this plasma is so thin and diffuse, the average temperature around the Voyager probes remains extremely cold.

In addition, Voyager 2 confirmed that the heliopause is one leaky border—and the leaks go both ways. Before Voyager 1 passed through the heliopause, it zoomed through tendrils of interstellar particles that had punched into the heliopause like tree roots through rock. Voyager 2, however, saw a trickle of low-energy particles that extended more than a hundred million miles beyond the heliopause.

Another mystery appeared as Voyager 1 came within 800 million miles of the heliopause, where it entered a limbo-like area in which the outbound solar wind slowed to a crawl. Before it crossed the heliopause, Voyager 2 saw the solar wind form an altogether different kind of layer that, oddly, was nearly the same width as the stagnant one seen by Voyager 1.

“That is very, very weird,” Koehn says. “It really shows us that we need more data.”

Interstellar sequel?

Solving these puzzles will require a better view of the heliosphere as a whole. Voyager 1 exited near the heliosphere’s leading edge, where it collides with the interstellar medium, and Voyager 2 exited along its left flank. We have no data on the heliosphere’s wake, so its overall shape remains a mystery. The interstellar medium’s pressure might keep the heliosphere roughly spherical, but it’s also possible that it has a tail like a comet—or that it is shaped like a croissant .

But while other spacecraft are currently outward bound, they won’t be able to return data from the heliopause. NASA’s New Horizons spacecraft is zooming out of the solar system at more than 31,000 miles an hour , and when it runs out of power in the 2030s, it’ll fall silent more than a billion miles short of the heliosphere’s outer edge. That’s why Voyager scientists and others are calling for a follow-up interstellar probe . The goal: a 50-year, multi-generation mission that explores the outer solar system on its way into unexplored regions beyond the solar wind.

“Here's an entire bubble, [and] we only crossed it with two points,” study coauthor Stamatios Krimigis , the emeritus head of the Johns Hopkins University Applied Physics Laboratory's space department, said at the briefing. “Two examples are not enough.”

A new generation of scientists is eager to run with the baton—including Rankin, who did her Ph.D. at Caltech with Voyager 1’s interstellar data with Stone as her adviser.

“It was amazing to work on this cutting-edge data from spacecraft that were launched before I was born and still doing amazing science,” she says. “I’m just really thankful for all the people who have spent so much time on Voyager.”

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Voyager 2 illuminates boundary of interstellar space.

Anthony Greicius

Pushing through plasma, leaking particles, magnetic field mystery.

One year ago, on Nov. 5, 2018, NASA’s Voyager 2 became only the second spacecraft in history to leave the heliosphere — the protective bubble of particles and magnetic fields created by our Sun. At a distance of about 11 billion miles (18 billion kilometers) from Earth — well beyond the orbit of Pluto — Voyager 2 had entered interstellar space, or the region between stars. Today, five new research papers in the journal Nature Astronomy describe what scientists observed during and since Voyager 2’s historic crossing.

Each paper details the findings from one of Voyager 2’s five operating science instruments: a magnetic field sensor, two instruments to detect energetic particles in different energy ranges and two instruments for studying plasma (a gas composed of charged particles). Taken together, the findings help paint a picture of this cosmic shoreline, where the environment created by our Sun ends and the vast ocean of interstellar space begins.

The Sun’s heliosphere is like a ship sailing through interstellar space. Both the heliosphere and interstellar space are filled with plasma, a gas that has had some of its atoms stripped of their electrons. The plasma inside the heliosphere is hot and sparse, while the plasma in interstellar space is colder and denser. The space between stars also contains cosmic rays, or particles accelerated by exploding stars. Voyager 1 discovered that the heliosphere protects Earth and the other planets from more than 70% of that radiation.

When Voyager 2 exited the heliosphere last year , scientists announced that its two energetic particle detectors noticed dramatic changes: The rate of heliospheric particles detected by the instruments plummeted, while the rate of cosmic rays (which typically have higher energies than the heliospheric particles) increased dramatically and remained high. The changes confirmed that the probe had entered a new region of space.

Before Voyager 1 reached the edge of the heliosphere in 2012, scientists didn’t know exactly how far this boundary was from the Sun. The two probes exited the heliosphere at different locations and also at different times in the constantly repeating, approximately 11-year solar cycle, over the course of which the Sun goes through a period of high and low activity. Scientists expected that the edge of the heliosphere, called the heliopause, can move as the Sun’s activity changes, sort of like a lung expanding and contracting with breath. This was consistent with the fact that the two probes encountered the heliopause at different distances from the Sun.

The new papers now confirm that Voyager 2 is not yet in undisturbed interstellar space: Like its twin, Voyager 1, Voyager 2 appears to be in a perturbed transitional region just beyond the heliosphere.

“The Voyager probes are showing us how our Sun interacts with the stuff that fills most of the space between stars in the Milky Way galaxy,” said Ed Stone, project scientist for Voyager and a professor of physics at Caltech. “Without this new data from Voyager 2, we wouldn’t know if what we were seeing with Voyager 1 was characteristic of the entire heliosphere or specific just to the location and time when it crossed.”

The two Voyager spacecraft have now confirmed that the plasma in local interstellar space is significantly denser than the plasma inside the heliosphere, as scientists expected. Voyager 2 has now also measured the temperature of the plasma in nearby interstellar space and confirmed it is colder than the plasma inside the heliosphere.

In 2012, Voyager 1 observed a slightly higher-than-expected plasma density just outside the heliosphere, indicating that the plasma is being somewhat compressed. Voyager 2 observed that the plasma outside the heliosphere is slightly warmer than expected, which could also indicate it is being compressed. (The plasma outside is still colder than the plasma inside.) Voyager 2 also observed a slight increase in plasma density just before it exited the heliosphere, indicating that the plasma is compressed around the inside edge of the bubble. But scientists don’t yet fully understand what is causing the compression on either side.

If the heliosphere is like a ship sailing through interstellar space, it appears the hull is somewhat leaky. One of Voyager’s particle instruments showed that a trickle of particles from inside the heliosphere is slipping through the boundary and into interstellar space. Voyager 1 exited close to the very “front” of the heliosphere, relative to the bubble’s movement through space. Voyager 2, on the other hand, is located closer to the flank, and this region appears to be more porous than the region where Voyager 1 is located.

An observation by Voyager 2’s magnetic field instrument confirms a surprising result from Voyager 1: The magnetic field in the region just beyond the heliopause is parallel to the magnetic field inside the heliosphere. With Voyager 1, scientists had only one sample of these magnetic fields and couldn’t say for sure whether the apparent alignment was characteristic of the entire exterior region or just a coincidence. Voyager 2’s magnetometer observations confirm the Voyager 1 finding and indicate that the two fields align, according to Stone.   

The Voyager probes launched in 1977, and both flew by Jupiter and Saturn. Voyager 2 changed course at Saturn in order to fly by Uranus and Neptune, performing the only close flybys of those planets in history. The Voyager probes completed their Grand Tour of the planets and began their Interstellar Mission to reach the heliopause in 1989. Voyager 1, the faster of the two probes, is currently over 13.6 billion miles (22 billion kilometers) from the Sun, while Voyager 2 is 11.3 billion miles (18.2 billion kilometers) from the Sun. It takes light about 16.5 hours to travel from Voyager 2 to Earth. By comparison, light traveling from the Sun takes about eight minutes to reach Earth.

More information about Voyager is available at the following site:

https://voyager.jpl.nasa.gov/

Calla Cofield Jet Propulsion Laboratory, Pasadena, Calif. 626-808-2469 [email protected]

Interstellar Mission

The Voyager 2 spacecraft, which has been in operation since 1977 and is the only spacecraft to have ever visited Uranus and Neptune, has made its way to interstellar space, where its twin spacecraft, Voyager 1, has resided since August 2012.

Mission Statistics

Launch Date

Aug. 20, 1977

About the mission

The Voyager 2 spacecraft, which has been in operation since 1977 and is the only spacecraft to have ever visited Uranus and Neptune, has made its way to interstellar space, where its twin spacecraft, Voyager 1, has resided since August 2012. During its travels through the outer solar system, Voyager 2 visited all four gas giant planets, and also discovered and photographed many of the planets' moons.

The spacecraft's flyby of Neptune in 1989 set it on a course below the elliptic plane that eventually took it to interstellar space on November 5, 2018. In 1998, engineers switched off the spacecraft's nonessential instruments to conserve power. Data from at least some of the six instruments still in operation should be received until at least 2025.

Instruments

• Imaging system
• Infrared interferometer spectrometer
• Ultraviolet spectrometer
• Triaxial fluxgate magnetometer
• Plasma spectrometer
• Low-energy charged particles detectors
• Cosmic Ray System (CRS)
• Photopolarimeter System (PPS)
• Plasma Wave System (PWS)

Mission Highlights

Nov. 5, 2018

Interactive 3D model of Voyager 2.View the full interactive experience at Eyes on the Solar System .

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Average speed cameras to enforce new 40mph speed limit on motorway

The temporary average speed cameras will enforce the speed limit as resurfacing work continues.

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New average speed cameras will begin enforcing a 40mph speed limit on a section of the M8 in Glasgow from Tuesday for several months.

The temporary average speed cameras will enforce the speed limit between junction 13 and 14 of the motorway as resurfacing work continues.

Amey, on behalf of Transport Scotland, are undertaking essential resurfacing on the M8 eastbound between junctions 14 and 13, which includes the M80 off-slip road at junction 1.

The work began on February 12 and is expected to continue over the coming months.

During this time Temporary Average Speed Cameras at Roadworks (TASCAR) systems will be enforcing the temporary speed limits for the safety of road users and road workers. 

Much of the work is carried out through the night by the road workers, when there is less traffic moving through the area, and this is the time when speeding offences are found to be at their highest. 

TASCAR are shown to control speeds over a greater distance in areas of roadworks, reducing heavy braking and acceleration, and in turn improving road safety. 

This scheme will benefit around 32,000 road users each day, by improving the condition of the carriageway and reducing the need for more extensive maintenance in the future.

Further information on Safety Cameras Scotland and camera locations can be found at safetycameras.gov.scot .

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What to know about the cargo ship Dali, a mid-sized ocean monster that took down a Baltimore bridge

Crews were set to begin removing the wreckage of a collapsed highway bridge in Baltimore on Friday. Maryland Gov. Wes Moore said a large crane, which can lift up to 1,000 tons, would be one of at least two used to clear the channel of the twisted metal and concrete remains of the Francis Scott Key Bridge, and the cargo ship that collided with it this week.

The container ship Dali, owned by Grace Ocean PTE, rests against wreckage of the Francis Scott Key Bridge in the Patapsco River on Wednesday, March 27, 2024, as seen from Pasadena, Md. Investigators began collecting evidence Wednesday from the cargo ship that plowed into Baltimore’s Francis Scott Key Bridge and caused its collapse, while in the waters below divers searched through twisted metal for several construction workers who plunged into the harbor and were feared dead. (AP Photo/Alex Brandon)

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In this image taken from video released by the National Transportation and Safety Board, the cargo ship Dali is stuck under part of the structure of the Francis Scott Key Bridge after the ship hit the bridge, Tuesday, March 26, 2024, in Baltimore. (NTSB via AP)

Here’s what to know about the cargo ship Dali that crashed into Baltimore’s Francis Scott Key Bridge, causing it to collapse and leaving six bridge construction workers presumed dead.

MONSTERS OF THE OCEAN

If stood upright, the Dali would reach almost to the top of the Eiffel Tower in Paris or about two-thirds of the way up the Empire State Building in New York.

It can carry the equivalent of almost 10,000 standard-sized metal shipping containers, and at the time of the accident was carrying nearly 4,700 containers. But while those figures are impressive, the Dali pales in comparison to the world’s largest container ships, which can carry more than 24,000 containers. There are environmental and economic advantages to operating giant container ships , but their sheer size and weight make them difficult to maneuver and stop — especially when something goes wrong.

Dali length: 984 feet (300 meters). Weight: 95,000 tons when empty.

Capacity: 10,000 20-foot (6-meter) containers.

MAYDAY CALL SAVES LIVES

The ship shares a name with one of history’s most celebrated artists, Spanish surrealist painter Salvador Dali.

Built by South Korea’s Hyundai Heavy Industries, one of the world’s largest shipbuilders, the Dali was launched in late 2014. It’s owned by Grace Ocean Private Ltd, flies a Singapore flag and is powered by diesel engines.

Danish shipping giant Maersk had chartered the Dali for a planned trip from Baltimore to Sri Lanka, but the ship didn’t get far, with the crew sending a mayday call early Tuesday saying they had lost power and had no control of the steering system. Minutes later, the ship rammed one of the bridge’s columns, causing the entire structure to collapse within seconds.

The ship was moving at about 8 knots, or 9 mph (15 kph). The mayday gave just enough time for authorities to stop bridge traffic and likely prevent more deaths , but not enough time to clear the construction crew that was filling potholes on the bridge. Divers on Wednesday recovered the bodies of two of the workers.

All of the nearly two dozen crew members from the Dali were accounted for after the accident, with one taken to a hospital with minor injuries.

PASSED PREVIOUS INSPECTIONS

The Dali passed a June 2023 inspection in Chile. A faulty pressure gauge for the fuel heaters was identified but fixed before the vessel left the port, according to authorities. The Dali was then inspected in September by the U.S. Coast Guard in New York, and no problems were found. Before it left Baltimore, the ship underwent routine engine maintenance, according to the Coast Guard.

The container ship Dali, owned by Grace Ocean PTE, rests against wreckage of the Francis Scott Key Bridge in the Patapsco River on Wednesday, March 27, 2024, as seen from Pasadena, Md. (AP Photo/Alex Brandon)

Federal and state officials say the crash appears to be an accident.

The Coast Guard has downloaded the voyage data recorder and sent it to the National Transportation Safety Board, which is building a timeline of what led to the crash, and a preliminary report is expected in the coming weeks. Singapore also plans to carry out its own investigation, which it says will be to identify lessons for the future rather than determine liability.

WHAT’S NEXT

In addition to trying to clear the channel floor of the bridge debris, officials will need to assess the damage to the Dali and make sure it doesn’t leak fuel or sink. Investigators found damage to at least 13 containers on the ship.

The Dali will then likely be towed back to the port and the cargo offloaded.

Transportation Secretary Pete Buttigieg says it’s too early to say how long it will take to reopen the Port of Baltimore or replace the destroyed bridge. He noted it initially took five years to build the bridge .

Baltimore bridge collapse: What happened and what is the death toll?

What is the death toll, when did the baltimore bridge collapse, why did the bridge collapse, who will pay for the damage and how much will the bridge cost.

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Writing by Lisa Shumaker; Editing by Daniel Wallis and Bill Berkrot

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Lisa's journalism career spans two decades, and she currently serves as the Americas Day Editor for the Global News Desk. She played a pivotal role in tracking the COVID pandemic and leading initiatives in speed, headline writing and multimedia. She has worked closely with the finance and company news teams on major stories, such as the departures of Twitter CEO Jack Dorsey and Amazon’s Jeff Bezos and significant developments at Apple, Alphabet, Facebook and Tesla. Her dedication and hard work have been recognized with the 2010 Desk Editor of the Year award and a Journalist of the Year nomination in 2020. Lisa is passionate about visual and long-form storytelling. She holds a degree in both psychology and journalism from Penn State University.

Investigation into Peru's Boluarte widened to include Cartier bracelet, bank deposits

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• 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

Did You Know?

The Voyager mission was officially approved in May 1972. Through the dedicated efforts of many skilled personnel for over three decades, the Voyagers have returned knowledge about the outer planets that had not existed in all of the preceding history of astronomy and planetary science. The Voyager spacecrafts are still performing like champs.

It must come as no surprise that there are many remarkable, "gee-whiz" facts associated with the various aspects of the Voyager mission. These tidbits have been summarized below in appropriate categories. Several may seem difficult to believe, but they are all true and accurate.

Overall Mission

The total cost of the Voyager mission from May 1972 through the Neptune encounter (including launch vehicles, radioactive power source (RTGs), and DSN tracking support) is 865 million dollars. At first, this may sound very expensive, but the fantastic returns are a bargain when we place the costs in the proper perspective. It is important to realize that:

• on a per-capita basis, this is only 8 cents per U.S. resident per year, or roughly half the cost of one candy bar each year since project inception. the entire cost of Voyager is a fraction of the daily interest on the U.S. national debt.
• A total of 11,000 workyears was devoted to the Voyager project through the Neptune encounter. This is equivalent to one-third the amount of effort estimated to complete the great pyramid at Giza to King Cheops.

A total of five trillion bits of scientific data had been returned to Earth by both Voyager spacecraft at the completion of the Neptune encounter. This represents enough bits to fill more than seven thousand music CDs.

The sensitivity of our deep-space tracking antennas located around the world is truly amazing. The antennas must capture Voyager information from a signal so weak that the power striking the antenna is only 10 exponent -16 watts (1 part in 10 quadrillion). A modern-day electronic digital watch operates at a power level 20 billion times greater than this feeble level.

Voyager Spacecraft

Each Voyager spacecraft comprises 65,000 individual parts. Many of these parts have a large number of "equivalent" smaller parts such as transistors. One computer memory alone contains over one million equivalent electronic parts, with each spacecraft containing some five million equivalent parts. Since a color TV set contains about 2500 equivalent parts, each Voyager has the equivalent electronic circuit complexity of some 2000 color TV sets.

Like the HAL computer aboard the ship Discovery from the famous science fiction story 2001: A Space Odyssey, each Voyager is equipped with computer programming for autonomous fault protection. The Voyager system is one of the most sophisticated ever designed for a deep-space probe. There are seven top-level fault protection routines, each capable of covering a multitude of possible failures. The spacecraft can place itself in a safe state in a matter of only seconds or minutes, an ability that is critical for its survival when round-trip communication times for Earth stretch to several hours as the spacecraft journeys to the remote outer solar system.

Both Voyagers were specifically designed and protected to withstand the large radiation dosage during the Jupiter swing-by. This was accomplished by selecting radiation-hardened parts and by shielding very sensitive parts. An unprotected human passenger riding aboard Voyager 1 during its Jupiter encounter would have received a radiation dose equal to one thousand times the lethal level.

The Voyager spacecraft can point its scientific instruments on the scan platform to an accuracy of better than one-tenth of a degree. This is comparable to bowling strike-after-strike ad infinitum, assuming that you must hit within one inch of the strike pocket every time. Such precision is necessary to properly center the narrow-angle picture whose square field-of-view would be equivalent to the width of a bowling pin.

To avoid smearing in Voyager's television pictures, spacecraft angular rates must be extremely small to hold the cameras as steady as possible during the exposure time. Each spacecraft is so steady that angular rates are typically 15 times slower than the motion of a clock's hour hand. But even this was not steady enough at Neptune, where light levels are 900 times fainter than those on Earth. Spacecraft engineers devised ways to make Voyager 30 times steadier than the hour hand on a clock.

The electronics and heaters aboard each nearly one-ton Voyager spacecraft can operate on only 400 watts of power, or roughly one-fourth that used by an average residential home in the western United States.

A set of small thrusters provides Voyager with the capability for attitude control and trajectory correction. Each of these tiny assemblies has a thrust of only three ounces. In the absence of friction, on a level road, it would take nearly six hours to accelerate a large car up to a speed of 48 km/h (30 mph) using one of the thrusters.

The Voyager scan platform can be moved about two axes of rotation. A thumb-sized motor in the gear train drive assembly (which turns 9000 revolutions for each single revolution of the scan platform) will have rotated five million revolutions from launch through the Neptune encounter. This is equivalent to the number of automobile crankshaft revolutions during a trip of 2725 km (1700 mi), about the distance from Boston,MA to Dallas,TX.

The Voyager gyroscopes can detect spacecraft angular motion as little as one ten-thousandth of a degree. The Sun's apparent motion in our sky moves over 40 times that amount in just one second.

The tape recorder aboard each Voyager has been designed to record and playback a great deal of scientific data. The tape head should not begin to wear out until the tape has been moved back and forth through a distance comparable to that across the United States. Imagine playing a two-hour video cassette on your home VCR once a day for the next 33 years, without a failure.

The Voyager magnetometers are mounted on a frail, spindly, fiberglass boom that was unfurled from a two-foot-long can shortly after the spacecraft left Earth. After the boom telescoped and rotated out of the cannister to an extension of nearly 13 meters (43 feet), the orientations of the magnetometer sensors were controlled to an accuracy better than two degrees.

Each Voyager used the enormous gravity field of Jupiter to be hurled on to Saturn, experiencing a Sun-relative speed increase of roughly 35,700 mph. As total energy within the solar system must be conserved, Jupiter was initially slowed in its solar orbit---but by only one foot per trillion years. Additional gravity-assist swing-bys of Saturn and Uranus were necessary for Voyager 2 to complete its Grand Tour flight to Neptune, reducing the trip time by nearly twenty years when compared to the unassisted Earth-to-Neptune route.

The Voyager delivery accuracy at Neptune of 100 km (62 mi), divided by the trip distance or arc length traveled of 7,128,603,456 km (4,429,508,700 mi), is equivalent to the feat of sinking a 3630 km (2260 mi) golf putt, assuming that the golfer can make a few illegal fine adjustments while the ball is rolling across this incredibly long green.

Voyager's fuel efficiency (in terms of mpg) is quite impressive. Even though most of the launch vehicle's 700 ton weight is due to rocket fuel, Voyager 2's great travel distance of 7.1 billion km (4.4 billion mi) from launch to Neptune resultsed in a fuel economy of about 13,000 km per liter (30,000 mi per gallon). As Voyager 2 streaked by Neptune and coasts out of the solar system, this fuel economy just got better and better!

The resolution of the Voyager narrow-angle television cameras is sharp enough to read a newspaper headline at a distance of 1 km (0.62 mi).

Pele, the largest of the volcanoes seen on Jupiter's moon Io, is throwing sulfur and sulfur-dioxide products to heights 30 times that of Mount Everest, and the fallout zone covers an area the size of France. The eruption of Mount St. Helens was but a tiny hiccup in comparison (admittedly, Io's surface-level gravity is some six times weaker than that of Earth).

The smooth water-ice surface of Jupiter's moon Europa may hide an ocean beneath, but some scientists believe any past oceans have turned to slush or ice. In 2010: Odyssey Two, Arthur C. Clarke wraps his story around the possibility of life developing within the oceans of Europa.

The rings of Saturn appeared to the Voyagers as a dazzling necklace of 10,000 strands. Trillions of ice particles and car-sized bergs race along each of the million-kilometer-long tracks, with the traffic flow orchestrated by the combined gravitational tugs of Saturn, a retinue of moons and moonlets, and even nearby ring particles. The rings of Saturn are so thin in proportion to their 171,000 km (106,000 mi) width that, if a full-scale model were to be built with the thickness of a phonograph record the model would have to measure four miles from its inner edge to its outer rim. An intricate tapestry of ring-particle patterns is created by many complex dynamic interactions that have spawned new theories of wave and particle motion.

Saturn's largest moon Titan was seen as a strange world with its dense atmosphere and variety of hydrocarbons that slowly fall upon seas of ethane and methane. To some scientists, Titan, with its principally nitrogen atmosphere, seemed like a small Earth whose evolution had long ago been halted by the arrival of its ice age, perhaps deep-freezing a few organic relics beneath its present surface.

The rings of Uranus are so dark that Voyager's challenge of taking their picture was comparable to the task of photographing a pile of charcoal briquettes at the foot of a Christmas tree, illuminated only by a 1 watt bulb at the top of the tree, using ASA-64 film. And Neptune light levels will be less than half those at Uranus.

Through the ages, astronomers have argued without agreeing on where the solar system ends. One opinion is that the boundary is where the Sun’s gravity no longer dominates – a point beyond the planets and beyond the Oort Cloud. This boundary is roughly about halfway to the nearest star, Proxima Centauri. Traveling at speeds of over 35,000 miles per hour, it will take the Voyagers nearly 40,000 years, and they will have traveled a distance of about two light years to reach this rather indistinct boundary.

But there is a more definitive and unambiguous frontier, which the Voyagers will approach and pass through. This is the heliopause, which is the boundary area between the solar and the interstellar wind. When Voyager 1 crosses the solar wind termination shock, it will have entered into the heliosheath, the turbulent region leading up to the heliopause. When the Voyagers cross the heliopause, hopefully while the spacecraft are still able to send science data to Earth, they will be in interstellar space even though they will still be a very long way from the “edge of the solar system”. Once Voyager is in interstellar space, it will be immersed in matter that came from explosions of nearby stars. So, in a sense, one could consider the heliopause as the final frontier.

Barring any serious spacecraft subsystem failures, the Voyagers may survive until the early twenty-first century (~ 2025), when diminishing power and hydrazine levels will prevent further operation. Were it not for these dwindling consumables and the possibility of losing lock on the faint Sun, our tracking antennas could continue to "talk" with the Voyagers for another century or two!