Win a Copy of “Hubble’s Universe: Greatest Discoveries and Latest Images”

A beautiful new book, “Hubble’s Universe: Greatest Discoveries and Latest Images” provides the history of the iconic Hubble Space Telescope, explaining some of the greatest discoveries in astronomy. But it’s also a stunning picture book, including some stunning, previously unpublished images from HST. You can see a gallery of some of those images here, and read our full review of the book here.

Thanks to Firefly Books, Universe Today has a copy of this book to giveaway!

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Book Review: “Hubble’s Universe: Greatest Discoveries and Latest Images”

The Hubble Space Telescope has been the subject of several books and articles, and certainly much more will be written about it in the future, as its status as the world’s most successful science experiment will guarantee that. And though breathtaking images are what hooks many people on the telescope, the Hubble was designed and built to do more than just take pretty pictures. The Hubble was planned and built to shed light on several different issues in astronomy and cosmology.

A new book, “Hubble’s Universe: Greatest Discoveries and Latest Images,” by Terence Dickinson, explains the important contributions Hubble has made in the areas of galactic evolution, dark matter and dark energy, and the expansion rate of the Universe. After a quick recounting of the Hubble’s launch and its well-documented initial problems, the author spells out Hubble’s top discoveries, including Hubble’s contribution to our understanding of the super-massive black holes at the centre of galaxies and our first looks at the atmospheres of extra-solar planets.

But the book is more than just clear and readable explanations of discoveries in astronomy. It’s a stunning picture book, equally at home in the living room as it is in the study. The array of pictures is simply awesome, and as Universe Today readers know, astronomy photos can suck anyone in.

See a gallery of new images from the book here.

Find out how you can win a copy of this book here.
The Hubble Space Telescope and the people that work with it are responsible for the images in this book, but it takes a special person to put a book like this together. The author, Terence Dickinson, is well-known in astronomy circles. If you don’t know who he is, you should. He’s the author of the top-selling star-gazing guide in the world, “NightWatch: A Practical Guide to Viewing the Universe,” as well as 14 other books. He’s won numerous awards for science-writing and for the popularization of science. An accomplished astro-photographer, one of his photos of the Moon has been on a U.S. postage stamp. He’s even been awarded the Order of Canada, the country’s second highest honour for merit. Terence Dickinson has a healthy passion for science, and has spent his life igniting that passion in others.

“Hubble’s Universe” is loaded with hundreds of photos of the kind we’ve become used to from Hubble, and some in the book have never before been published (see some of them here). The beauty of glowing gas clouds, the rich luminescence of filaments of gas and dust in distant nebulae, the beauty of the planets in our own solar system. This book is basically a feast of astrophotography.

While many books have been written about Hubble, this one will stack up against any of them. All Hubble books have stunning images in them, but what makes this one special is Dickinson’s ability for explanation. The writing is very accessible while still doing an outstanding job of handling some difficult subjects. If you’ve ever struggled with explanations of things like Dark Matter and Dark Energy, “Hubble’s Universe” will bring clarity, without any dumbing down of the subject matter.

You won’t regret buying this book, for yourself or perhaps for someone else. It’s destined to be a staple in libraries and astronomy collections. I’ll be bold and go a little further. “Hubble’s Universe” is destined to be a classic much like some of Dickinson’s other books.

Here’s a video of Dickinson discussing Hubble and his new book:

40 Years After Apollo, the Moon Still Beckons

A lunar mining facility harvests oxygen from the resource-rich volcanic soil of the eastern Mare Serenitatis.Credit: NASA/Pat Rawlings

40 years ago this week, the final Apollo mission, Apollo 17, launched to the Moon. In this new video produced by author Andrew Chaikin, geologist Paul Spudis of the Lunar and Planetary Institute explains why the Moon still beckons, “not just to visit, not just put a footprint there, but to go and understand it, to collect its rock and understand its history, to recover a lost chapter of a previous existence.” Right now, we understand just a small part of the history of our Solar System, and the Moon holds that history in its rocks. Additionally, newly found water on the Moon — estimates say about 600 million metric tons could be at the lunar poles — could allow us to “live off the land” in space.

A lunar mining facility harvests oxygen from the resource-rich volcanic soil of the eastern Mare Serenitatis. Credit: NASA/Pat Rawlings.

Geminid Meteor Shower and Meteorwatch

Credit: VirtualAstro

The Geminid Meteor Shower is the grand finale of astronomical events in 2012 and is usually the most reliable and prolific of the annual meteor showers.

This year we are in for a special treat as the Moon will be absent when the Geminids are at their peak on the evening of the 12th/ 13th of December. This means that the sky should be at its darkest when the shower is expected, and many more of the fainter meteors may be seen.

The Geminid meteor shower is expected to yield in excess of 50 meteors (shooting stars) per hour at peak for those with clear skies, the meteors it produces are usually bright with long persistent trains. If observing opportunities aren’t favorable or possible on the 12th/ 13th, meteor watchers can usually see high meteor activity a day or so either side of the peak.

As well as being the grand finale of 2012, the Geminids are special in another way. Unlike the majority of all the other annual meteor showers the Geminids are thought to be from an object known as 3200 Phaethon – an asteroid not a comet.

To celebrate this long anticipated event, there will be the Geminid Meteorwatch and anyone with an interest in the night sky can join in on Twitter, Facebook and Google+. The event will be an excellent opportunity to learn, share information, experiences, images and more. Whatever your level of interest, wherever you are on the planet Meteorwatch will run for approximately four days. All you need to do is follow along using the #meteorwatch hashtag.

As well as the wealth of information exchanged and shared on Twitter and the other social media outlets, there are helpful guides and information available on so you can get the most out of your #meteorwatch.
To get the ball rolling there is a Hollywood style trailer for the event, purely as a bit of fun and for people of all walks of life to feel inspired and to go outside and look up. You don’t need a telescope or anything, just your eyes and a little bit of patience to see a Geminid meteor.

Good luck

Opportunity Rover Glimpses Conditions Suitable for Life

Whitewater Lake is the large flat rock in the top half of the image. From left to right it is about 30 inches (0.8 meter) across. The dark blue nubby rock to the lower left is “Kirkwood,” which bears non-hematite spherules. Credit: NASA/JPL-Caltech/ Cornell Univ./Arizona State Univ.

Steve Squyres, Principal Investigator for the Mars Explorations Rovers, cracked open the equivalent of the Opportunity rover’s field geologist’s notebook to describe what he called “a delightful geological puzzle.”

“This is a work in progress,” Squyres said at the American Geophsical Union conference today, “But this is our first glimpse ever at conditions on ancient Mars that clearly show us a chemistry that would have been suitable for life.”

While both the MER rovers have found evidence of past water on Mars, all indications are that it would have been very acidic, with “battery-acid kind of numbers making it very challenging for life,” Squyres said.

Newly found clays that are sprinkled with two different kinds of previously unseen features point to a different type of water “that you could drink,” Sqyures added.

Orbital data from the Mars Reconnaissance Orbiter’s CRISM (Compact Reconnaissance Imaging Spectrometer for Mars) instrument originally led the MER team to Endeavour Crater, the huge crater where Opportunity is now traversing around the rim.

“It was discovered from CRISM that there were clay minerals there,” Squyres said, “and clays form in a watery environment, and only form under a neutral pH, water that is not acidic.”

The rover has found a region filled with light-toned rocks, such as the Whitewater Lake rock, above, around a small hill named “Matijevic Hill” in the “Cape York” segment of the rim of Endeavour Crater. Squyres described it as the “sweet spot” where clays are known to be present.

This map shows the route driven by NASA’s Mars Exploration Rover Opportunity during a reconnaissance circuit around an area of interest called “Matijevic Hill” on the rim of a large crater. Image credit: NASA/JPL-Caltech/University of Arizona

They have since driven the rover around Matijevic Hill to survey the clays, “which is what you would do if you were a geologist at a site, you’d walk the outcrop,” Squyres said. “We’ve got a good map of where the good, interesting stuff is at Matijevic Hill.”

Interspersed on the light-toned rocks are fine veins of even lighter material, which has never been seen before. Additionally, there are “fins” of darker rock sticking up in the region, and within the fins are dense concentrations of spherical little features, about 3 mm in size that are very similar to the hematite Martian “blueberries” that Opportunity has seen before. But when they looked at the chemical composition of these spheres, the science team found they weren’t blueberries, because they contained no iron, which is what hematite is made from.

“It’s something totally different, and I’ve started calling them ‘newberries’,” said Squyres.

Small spherical objects fill the field in this mosaic combining four images from the Microscopic Imager on NASA’s Mars Exploration Rover Opportunity. Image credit: NASA/JPL-Caltech/Cornell Univ./ USGS/Modesto Junior College

It is difficult for the rover to determine the chemical make-up of the newberries and the light-colored veins because they are such small features, the rover can’t focus merely on those features. But Squyres and team have come up with a to-do list to try and figure out the mystery of the clays and newberries:

Task one is to understand the Whitewater Lake rock better and look at the rock’s sediments, to understand the layers in the rock: were the layers laid down by water, impact or another process?

The second task is to figure out what the newberries made of. They will have to observe regions that have different concentrations of the spherules to eke out what minerals are and aren’t part of the newberries.

Task three is to find a “contact place” where the light-toned clay rocks like Whitewater are touching the breccias – the broken and fused rock born of the impact that created the crater – that is present all around the rim of Endeavour. They haven’t yet found a place where the two are together.

Task four is to figure out what the fine veins are in the clay rocks.

The tasks are intertwined, Squyres said. “Figuring out the newberries will be important for figuring out the how these clays were laid down. So the stories aren’t independent, they are woven together and we still have homework to do,” he said.

But the team will have to work fast.

Opportunity image of light, flat rocks containing clay and mysterious darker rocks jutting through them. NASA/JPL-Caltech/ Cornell Univ./Arizona State Univ

They have about 6 months before winter sets in again in Meridiani Planum on Mars.

“We’ll soon start doing some serious winter planning,” said Diana Blaney, Deputy Project Scientist. When asked about the potential for Oppy to make it through another winter, Blaney said it all depends on the amount of dust build-up on the solar panels and how much power can be generated. “We don’t have any reason not to expect to survive, but it is a dynamic situation, and are looking ahead to find potential wintering sites,” that have beneficial tilt for the rover to absorb as much sunlight as possible.

The last winter the Opportunity rover endured was the first time the rover had to remain stationary due to power concerns because of dust accumulation on the solar arrays.

“We’re nine years into a 90 day mission,” Squyres said, “and every day is a gift at this point and we’re just going to keep pushing ourselves and the rover.”

A 3-D mosaic of the Cape York region where Opportunity is now working. Credit: NASA/JPL-Caltech/ Cornell Univ./Arizona State Univ

For additional information, see this NASA press release.

NASA Reveals Plans for New Mars Rover

Sequels are all the rage these days… even for NASA, apparently.

At the American Geophysical Union 2012 convention in San Francisco today, NASA’s associate administrator for science John Grunsfeld revealed the agency’s plans for another Mars mission. Slated to land in 2020, it will be a rover based on the same design as Mars Science Laboratory. Estimated cost of the mission was announced to be $1.5 billion.

This news brought mixed reactions from many of those in attendance as well as followers online, as while more exploration of the Red Planet is certainly an exciting concept, we have all heard — and seen — countless tales of budget cuts and funding problems throughout NASA over recent years, and many proposed missions and collaborations have had to be shelved or cut short due to lack of funds (remember ExoMars?) Even though the budget for this mission is supposedly “not being taken from other areas,” it’s clearly not going to them either. It will be interesting to see how this plays out across the agency.

The full press release from NASA can be seen below:

(Via NASA)

Building on the success of Curiosity’s Red Planet landing, NASA has announced plans for a robust multi-year Mars program, including a new robotic science rover set to launch in 2020. This announcement affirms the agency’s commitment to a bold exploration program that meets our nation’s scientific and human exploration objectives.

“The Obama administration is committed to a robust Mars exploration program,” NASA Administrator Charles Bolden said. “With this next mission, we’re ensuring America remains the world leader in the exploration of the Red Planet, while taking another significant step toward sending humans there in the 2030s.”

The planned portfolio includes the Curiosity and Opportunity rovers; two NASA spacecraft and contributions to one European spacecraft currently orbiting Mars; the 2013 launch of the Mars Atmosphere and Volatile EvolutioN (MAVEN) orbiter to study the Martian upper atmosphere; the Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) mission, which will take the first look into the deep interior of Mars; and participation in ESA’s 2016 and 2018 ExoMars missions, including providing “Electra” telecommunication radios to ESA’s 2016 mission and a critical element of the premier astrobiology instrument on the 2018 ExoMars rover.

The plan to design and build a new Mars robotic science rover with a launch in 2020 comes only months after the agency announced InSight, which will launch in 2016, bringing a total of seven NASA missions operating or being planned to study and explore our Earth-like neighbor.

The 2020 mission will constitute another step toward being responsive to high-priority science goals and the president’s challenge of sending humans to Mars orbit in the 2030s.

The future rover development and design will be based on the Mars Science Laboratory (MSL) architecture that successfully carried the Curiosity rover to the Martian surface this summer. This will ensure mission costs and risks are as low as possible, while still delivering a highly capable rover with a proven landing system. The mission will constitute a vital component of a broad portfolio of Mars exploration missions in development for the coming decade.

The mission will advance the science priorities of the National Research Council’s 2011 Planetary Science Decadal Survey and responds to the findings of the Mars Program Planning Group established earlier this year to assist NASA in restructuring its Mars Exploration Program.

“The challenge to restructure the Mars Exploration Program has turned from the seven minutes of terror for the Curiosity landing to the start of seven years of innovation,” Grunsfeld said. “This mission concept fits within current and projected Mars exploration budget, builds on the exciting discoveries of Curiosity, and takes advantage of a favorable launch opportunity.”

The specific payload and science instruments for the 2020 mission will be openly competed, following the Science Mission Directorate’s established processes for instrument selection. This process will begin with the establishment of a science definition team that will be tasked to outline the scientific objectives for the mission.

This mission fits within the five-year budget plan in the president’s Fiscal Year 2013 budget request, and is contingent on future appropriations.

Plans also will include opportunities for infusing new capabilities developed through investments by NASA’s Space Technology Program, Human Exploration and Operations Mission Directorate, and contributions from international partners.


NASA and John Grunsfeld will be hosting a follow-up press conference later today at AGU, which will be streamed live online at 7 p.m. EST/4 p.m. PST. Stay tuned for more information.


The Brightest Galaxies in the Universe Were Invisible… Until Now

Hubble images of six of the starburst galaxies first found by ESA’s Herschel Space Observatory (Keck data shown below each in blue)

Many of the brightest, most actively star-forming galaxies in the Universe were actually undetectable by Earth-based observatories, hidden from view by thick clouds of opaque dust and gas. Thanks to ESA’s Herschel space observatory, which views the Universe in infrared, an enormous amount of these “starburst” galaxies have recently been uncovered, allowing astronomers to measure their distances with the twin telescopes of Hawaii’s W.M. Keck Observatory. What they found is quite surprising: at least 767 previously unknown galaxies, many of them generating new stars at incredible rates.

Although nearly invisible at optical wavelengths these newly-found galaxies shine brightly in far-infrared, making them visible to Herschel, which can peer through even the densest dust clouds. Once astronomers knew where the galaxies are located, they were able to target them with Hubble and, most importantly, the two 10-meter Keck telescopes — the two largest optical telescopes in the world.

By gathering literally hundreds of hours of spectral data on the galaxies with the Keck telescopes, estimates of their distances could be determined as well as their temperatures and how often new stars are born within them.

“While some of the galaxies are nearby, most are very distant; we even found galaxies that are so far that their light has taken 12 billion years to travel here, so we are seeing them when the Universe was only a ninth of its current age,” said Dr. Caitlin Casey, Hubble fellow at the UH Manoa Institute for Astronomy and lead scientist on the survey. “Now that we have a pretty good idea of how important this type of galaxy is in forming huge numbers of stars in the Universe, the next step is to figure out why and how they formed.”

A representation of the distribution of nearly 300 starbursts in one 1.4 x 1.4 degree field of view.

The galaxies, many of them observed as they were during the early stages of their formation, are producing new stars at a rate of 100 to 500 a year — with a mass equivalent of several thousand Suns — hence the moniker “starburst” galaxy. By comparison the Milky Way galaxy only births one or two Sun-mass stars per year.

The reason behind this explosion of star formation in these galaxies is unknown, but it’s thought that collisions between young galaxies may be the cause.

Another possibility is that galaxies had much more gas and dust during the early Universe, allowing for much higher star formation rates than what’s seen today.

“It’s a hotly debated topic that requires details on the shape and rotation of the galaxies before it can be resolved,” said Dr. Casey.

Still, the discovery of these “hidden” galaxies is a major step forward in understanding the evolution of star formation in the Universe.

“Our study confirms the importance of starburst galaxies in the cosmic history of star formation. Models that try to reproduce the formation and evolution of galaxies will have to take these results into account.”

– Dr. Caitlin Casey, Hubble fellow at the UH Manoa Institute for Astronomy

“For the first time, we have been able to measure distances, star formation rates, and temperatures for a brand new set of 767 previously unidentified galaxies,” said Dr. Scott Chapman, a co-author on the studies. “The previous similar survey of distant infrared starbursts only covered 73 galaxies. This is a huge improvement.”

The papers detailing the results were published today online in the Astrophysical Journal.

Sources: W.M. Keck Observatory article and ESA’s news release.

Image credits: ESA–C. Carreau/C. Casey (University of Hawai’i); COSMOS field: ESA/Herschel/SPIRE/HerMES Key Programme; Hubble images: NASA, ESA. Inset image courtesy W. M. Keck Observatory.

Astrophoto: Jet Black Moon

Jet crossing the Moon on December 2, 2012. Credit: Sculptor Lil on Flickr

A little play on words for the headline, but we just had to share this great shot by astrophotographer Sculptor Lil from London, England!

Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.

Black Hole Jets Might Be Molded by Magnetism

Visible-light Hubble image of the jet emitted by the 3-billion-solar-mass black hole at the heart of galaxy M87 (Feb. 1998) Credit: NASA/ESA and John Biretta (STScI/JHU)

Even though black holes — by their definition and very nature — are the ultimate hoarders of the Universe, gathering and gobbling up matter and energy to the extent that not even light can escape their gravitational grip, they also often exhibit the odd behavior of flinging vast amounts of material away from them as well, in the form of jets that erupt hundreds of thousands — if not millions — of light-years out into space. These jets contain superheated plasma that didn’t make it past the black hole’s event horizon, but rather got “spun up” by its powerful gravity and intense rotation and ended up getting shot outwards as if from an enormous cosmic cannon.

The exact mechanisms of how this all works aren’t precisely known as black holes are notoriously tricky to observe, and one of the more perplexing aspects of the jetting behavior is why they always seem to be aligned with the rotational axis of the actively feeding black hole, as well as perpendicular to the accompanying accretion disk. Now, new research using advanced 3D computer models is supporting the idea that it’s the black holes’ ramped-up rotation rate combined with plasma’s magnetism that’s responsible for shaping the jets.

In a recent paper published in the journal Science, assistant professor at the University of Maryland Jonathan McKinney, Kavli Institute director Roger Blandford and Princeton University’s Alexander Tchekhovskoy report their findings made using computer simulations of the complex physics found in the vicinity of a feeding supermassive black hole. These GRMHD — which stands for General Relativistic Magnetohydrodynamic — computer sims follow the interactions of literally millions of particles under the influence of general relativity and the physics of relativistic magnetized plasmas… basically, the really super-hot stuff that’s found within a black hole’s accretion disk.

Read more: First Look at a Black Hole’s Feast

What McKinney et al. found in their simulations was that no matter how they initially oriented the black hole’s jets, they always eventually ended up aligned with the rotational axis of the black hole itself — exactly what’s been found in real-world observations. The team found that this is caused by the magnetic field lines generated by the plasma getting twisted by the intense rotation of the black hole, thus gathering the plasma into narrow, focused jets aiming away from its spin axes — often at both poles.

At farther distances the influence of the black hole’s spin weakens and thus the jets may then begin to break apart or deviate from their initial paths — again, what has been seen in many observations.

This “magneto-spin alignment” mechanism, as the team calls it, appears to be most prevalent with active supermassive black holes whose accretion disk is more thick than thin — the result of having either a very high or very low rate of in-falling matter. This is the case with the giant elliptical galaxy M87, seen above, which exhibits a brilliant jet created by a 3-billion-solar-mass black hole at its center, as well as the much less massive 4-million-solar-mass SMBH at the center of our own galaxy, Sgr A*.

Read more: Milky Way’s Black Hole Shoots Out Brightest Flare Ever

Using these findings, future predictions can be better made concerning the behavior of accelerated matter falling into the heart of our galaxy.

Read more on the Kavli Institute’s news release here.

Inset image: Snapshot of a simulated black hole system. (McKinney et al.) Source: The Kavli Institute for Particle Astrophysics and Cosmology (KIPAC)

Voyager 1 Riding on a Magnetic Highway Out of the Solar System

Artist concept of NASA’s Voyager 1 spacecraft exploring a new region in our solar system called the “magnetic highway.” Credit: NASA/JPL-Caltech

The Voyager 1 spacecraft has not left the solar system, as was speculated earlier this year, but has now entered a new region at the edge of the solar system that scientists didn’t even know was there. It appears to be a “highway” of magnetic particles, shepherding Voyager 1 out into interstellar space.

“When you’ve gone where nothing has gone before, you expect to make new discoveries,” said Arik Posner, Voyager Program Scientist at a press briefing today.

“This is really another exciting step in the Voyager journey of exploration,” said Project Scientist Ed Stone. “Voyager’s discovered a new region of the heliosphere that we had not realized was there. It’s a magnetic highway where the magnetic field of the Sun is connected to the outside. So it’s like a highway, letting particles in and out.”

This artist’s concept shows plasma flows around NASA’s Voyager 1 spacecraft as it approaches interstellar space. Image credit: NASA/JPL-Caltech/JHUAPL

The heliosphere is a huge bubble of charged particles, and previously the Sun’s lower-energy charged particles have dominated. Now, Voyager 1 is in a region where it is surrounded almost entirely from cosmic rays from outside our solar system,as the lower-energy particles appear to be zooming out and higher-energy particles from outside are streaming in.

The first indication that something new was happening was on July 28 of this year when the level of lower-energy particles originating from inside our Solar System dropped by half. However, in three days, the levels had recovered to near their previous levels. But then the bottom dropped out at the end of August.

The two Voyager spacecraft have been heading outward since their launches 16 days apart in 1977. Voyager 1 is now near the edge of the solar system, and Voyager 2 is not far behind. Scientists feel this new region at the far reaches of our solar system is the final area the spacecraft has to cross before reaching interstellar space.

The Voyager team infers this region is still inside our solar bubble because the direction of the magnetic field lines has not changed. The direction of these magnetic field lines is predicted to change when Voyager breaks through to interstellar space.

“We believe this is the last leg of our journey to interstellar space,” Stone said. “Our best guess is it’s likely just a few months to a couple years away. The new region isn’t what we expected, but we’ve come to expect the unexpected from Voyager.”

Since December 2004, when Voyager 1 crossed a point in space called the termination shock, the spacecraft has been exploring the heliosphere’s outer layer, called the heliosheath. In this region, the stream of charged particles from the Sun, known as the solar wind, abruptly slowed down from supersonic speeds and became turbulent. Voyager 1’s environment was consistent for about five and a half years. The spacecraft then detected that the outward speed of the solar wind slowed to zero.

The intensity of the magnetic field also began to increase at that time.

“If we had only looked at the particle data alone, we would have said well, we’re out, goodbye solar system,” said Stamatios Krimigis, principal investigator for Voyager’s low-energy charged particle instrument. “We need to look at what all the instruments are telling us, because nature is very imaginative, and Lucy pulled out the football again.”

That’s because the magnetic field direction has not yet changed to the expected north-south orientation of interstellar space.

“We’re quite confident that there’s really no reason to believe we’re outside the heliosphere,” said Leonard Burlaga, with the Voyager magnetometer team. “There’s no evidence that we have entered the interstellar magnetic field. We are in a magnetic region unlike any we’ve been in before — about 10 times more intense than before the termination shock. The magnetic field data turned out to be the key to pinpointing when we crossed the termination shock. And we expect these data will tell us when we first reach interstellar space.”

As for the future of the spacecraft, which are powered by plutonium 238, they each lose about 4 watts of power a year and by 2020, the science team will have to start turning off instruments in order to conserve power. By 2025, there will probably not be enough power for any of the instruments to run, but there will be enough power to “ping” the spacecraft and have it answer. But by that time, they should be well out of the solar system. However, the spacecraft likely won’t encounter much, as it would take about 40,000 years for one of the Voyagers to reach another star system.

Voyager 1 is the most distant human-made object, about 18 billion kilometers (11 billion miles) away from the Sun. The signal from Voyager 1 takes approximately 17 hours to travel to Earth. Voyager 2, the longest continuously operated spacecraft, is about 15 billion kilometers (9 billion miles) away from our Sun. While Voyager 2 has seen changes similar to those seen by Voyager 1, the changes are much more gradual. Scientists do not think Voyager 2 has reached the magnetic highway.

Sources: Press briefing, JPL