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Interstellar - Blog Posts
I watched Interstellar for the first time today (10th year anniversary) with my friend and proud to say that i managed to hold in the sniffles while my friend cannot
That movie hurt my soul, wtf was Christopher Nolan cooking back then
Don’t know if I trust the way Christopher Nolan writes women for him to be allowed to tackle anything Greek mythology related
INTERSTELLAR IN THEATERS!!!!!! YOU CAN FEEL YOUR BONES VIBRATE AS THE LADS GET SUCKED INTO A BLACK HOLE!!!
INTERSTELLAR IN THEATERS AHAHAHSHKRKEJSKWIAJEJROEOS
@inkscapedoodles !!!!!!!
OUGHHHHH INTERSTELLAR-
Interstellar interstellar interstellar interstellarrrrrr 0v0
Just saw it with @augmentedchordsofficial in theaters for the first time and I'm SCREEEEECHING!!!
Wehhh, it's such a beautiful metaphor for family and love all wrapped up in a science-y, black hole bow that's absolutely scrumptious to nom on!
YAYYYYYY
@inkscapedoodles so excited :D
What would you trade the pain for?
Love From The Other Side - Fall Out Boy
this little manoeuvre (transferring from bed to wheelchair to bathroom to wheelchair to bed) is gonna cost us eighty one years (the rest of my energy until after my fasting labs in five hours)
oh yeah what I meant by this! watched Interstellar with my brothers last night. two of them are science nerds! so well one has seen it and one hadn't before
so afterward I sat at a table with the one that hadn't priorly seen it and asked scale of 1 to 10 how realistic he felt it was. he got immediately hung up on the mathematics of the time as portrayed on screen, we jabbered about that for a while
... and second brother comes in. "Okay what you NEED to know," he says, and he's apparently talked this over with the fandom several times over, and he just takes off in this conversation and here I am sitting between two brothers who are going off about the science of well everything practically
inwardly I'm kinda making this face :D because I miss these sorts of arguments (and also I get to be a part of it)
and bro
okay yeah I could go into the whole wormholes and black hole/white hole and time shift and that sort of thing, it was a good conversation, but I'll save that for another time
and there was the whole me bringing up The Martian as more realistic and then us picking it apart too (tbh it's very good tho) but again not the point of tonight's tale
the point being
loved ones are so precious
loved ones are so precious when they're engaging in the thing they love
love languages can be arguing over science technicalities in science fiction and cinema
I love these people so much and I love that I get to be theirs.
bringing back the interstellar fandom one cranky science nerd at a time
bringing back the interstellar fandom one cranky science nerd at a time
Film suggestions??
hiii! I can't choose so here a bunch of my favorites films!
La la land
musical/romance
Fight Club
thriller/drama
Knives Out
mystery/comedy
Interstellar
sci-fi/adventure
Dune
sci-fi/adventure
Snowpiercer
sci-fi
V for Vendetta
action/thriller
The Green Knight
adventure/drama
The Dark Knigth
action/adventure
Zodiac
mystery
Pride and Prejudice
romance/drama
Tick, tick ...boom
drama/biography
Memento
mystery/thriller
Crisom Peak
horror/fantasy
Shutter Island
thriller/mystery
and so many more but I can't put it all! Hope you like it!
From an astronauts perspective, what is your opinion on movies like Interstellar and Gravity?
Out of all the theories and fantasies created around blackholes, which of them, in your opinion, do you think could come closest to reality?
NASA Science Show & Tell
This week, we’re at one of the biggest science conferences in the country, where our scientists are presenting new results from our missions and projects. It’s called the American Geophysical Union’s Fall Meeting.
Here are a few of the things we shared this week...
The Sun
A few months into its seven-year mission, Parker Solar Probe has already flown far closer to the Sun than any spacecraft has ever gone. The data from this visit to the Sun has just started to come back to Earth, and scientists are hard at work on their analysis.
Parker Solar Probe sent us this new view of the Sun’s outer atmosphere, the corona. The image was taken by the mission’s WISPR instrument on Nov. 8, 2018, and shows a coronal streamer seen over the east limb of the Sun. Coronal streamers are structures of solar material within the Sun's atmosphere, the corona, that usually overlie regions of increased solar activity. The fine structure of the streamer is very clear, with at least two rays visible. Parker Solar Probe was about 16.9 million miles from the Sun's surface when this image was taken. The bright object near the center of the image is Mercury, and the dark spots are a result of background correction.
Hurricane Maria
Using a satellite view of human lights, our scientists watched the lights go out in Puerto Rico after Hurricane Maria. They could see the slow return of electricity to the island, and track how rural and mountainous regions took longer to regain power.
In the spring, a team of scientists flew a plane over Puerto Rico’s forests, using a laser instrument to measure how trees were damaged and how the overall structure of the forests had changed.
Earth’s Ice
Our scientists who study Antarctica saw some surprising changes to East Antarctica. Until now, most of the continent’s melting has been on the peninsula and West Antarctica, but our scientists have seen glaciers in East Antarctica lose lots of ice in the last few years.
Our ICESat-2 team showed some of their brand new data. From the changing height of Antarctic ice to lagoons off the coast of Mexico, the little satellite has spent its first few months measuring our planet in 3D. The laser pulses even see individual ocean waves, in this graph.
Scientists are using our satellite data to track Adélie penguin populations, by using an unusual proxy -- pictures of their poop! Penguins are too small to be seen by satellites, but they can see large amounts of their poop (which is pink!) and use that as a proxy for penguin populations.
Asteroid Bennu
Our OSIRIS-REx mission recently arrived at its destination, asteroid Bennu. On approach, data from the spacecraft’s spectrometers revealed chemical signatures of water trapped in clay minerals. While Bennu itself is too small to have ever hosted liquid water, the finding indicates that liquid water was present at some time on Bennu’s parent body, a much larger asteroid.
We also released a new, detailed shape model of Bennu, which is very similar to our ground-based observations of Bennu’s shape. This is a boon to ground-based radar astronomy since this is our first validation of the accuracy of the method for an asteroid! One change from the original shape model is the size of the large boulder near Bennu’s south pole, nicknamed “Benben.” The boulder is much bigger than we thought and overall, the quantity of boulders on the surface is higher than expected. Now the team will make further observations at closer ranges to more accurately assess where a sample can be taken on Bennu to later be returned to Earth.
Jupiter
The Juno mission celebrated it’s 16th science pass of #Jupiter, marking the halfway point in data collection of the prime mission. Over the second half of the prime mission — science flybys 17 through 32 — the spacecraft will split the difference, flying exactly halfway between each previous orbit. This will provide coverage of the planet every 11.25 degrees of longitude, providing a more detailed picture of what makes the whole of Jupiter tick.
Mars
The Mars 2020 team had a workshop to discuss the newly announced landing site for our next rover on the Red Planet. The landing site...Jezero Crater! The goal of Mars 2020 is to learn whether life ever existed on Mars. It's too cold and dry for life to exist on the Martian surface today. But after Jezero Crater formed billions of years ago, water filled it to form a deep lake about the same size as Lake Tahoe. Eventually, as Mars' climate changed, Lake Jezero dried up. And surface water disappeared from the planet.
Interstellar Space
Humanity now has two interstellar ambassadors. On Nov. 5, 2018, our Voyager 2 spacecraft left the heliosphere — the bubble of the Sun’s magnetic influence formed by the solar wind. It’s only the second-ever human-made object to enter interstellar space, following its twin, Voyager 1, that left the heliosphere in 2012.
Scientists are especially excited to keep receiving data from Voyager 2, because — unlike Voyager 1 — its plasma science instrument is still working. That means we’ll learn brand-new information about what fills the space between the stars.
Learn more about NASA Science at science.nasa.gov.
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For the second time in history, a human-made object has reached the space between the stars. Our Voyager 2 probe now has exited the heliosphere – the protective bubble of particles and magnetic fields created by the Sun.
Comparing data from different instruments aboard the trailblazing spacecraft, mission scientists determined the probe crossed the outer edge of the heliosphere on Nov. 5. This boundary, called the heliopause, is where the tenuous, hot solar wind meets the cold, dense interstellar medium. Its twin, Voyager 1, crossed this boundary in 2012, but Voyager 2 carries a working instrument that will provide first-of-its-kind observations of the nature of this gateway into interstellar space.
Voyager 2 now is slightly more than 11 billion miles (18 billion kilometers) from Earth. Mission operators still can communicate with Voyager 2 as it enters this new phase of its journey, but information – moving at the speed of light – takes about 16.5 hours to travel from the spacecraft to Earth. By comparison, light traveling from the Sun takes about eight minutes to reach Earth.
Read more at https://go.nasa.gov/2QG2s16 or follow along with the mission @NASAVoyager on Twitter.
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Things That Go Bump in the Gamma Rays
Some people watch scary movies because they like being startled. A bad guy jumps out from around a corner! A monster emerges from the shadows! Scientists experience surprises all the time, but they’re usually more excited than scared. Sometimes theories foreshadow new findings — like when there’s a dramatic swell in the movie soundtrack — but often, discoveries are truly unexpected.
Scientists working with the Fermi Gamma-Ray Space Telescope have been jumping to study mysterious bumps in the gamma rays for a decade now. Gamma rays are the highest-energy form of light. Invisible to human eyes, they’re created by some of the most powerful and unusual events and objects in the universe. In celebration of Halloween, here are a few creepy gamma-ray findings from Fermi’s catalog.
Stellar Graveyards
If you were to walk through a cemetery at night, you’d expect to trip over headstones or grave markers. Maybe you’d worry about running into a ghost. If you could explore the stellar gravesite created when a star explodes as a supernova, you’d find a cloud of debris expanding into interstellar space. Some of the chemical elements in that debris, like gold and platinum, go on to create new stars and planets! Fermi found that supernova remnants IC 443 and W44 also accelerate mysterious cosmic rays, high-energy particles moving at nearly the speed of light. As the shockwave of the supernova expands, particles escape its magnetic field and interact with non-cosmic-ray particles to produce gamma rays.
Ghost Particles
But the sources of cosmic rays aren’t the only particle mysteries Fermi studies. Just this July, Fermi teamed up with the IceCube Neutrino Observatory in Antarctica to discover the first source of neutrinos outside our galactic neighborhood. Neutrinos are particles that weigh almost nothing and rarely interact with anything. Around a trillion of them pass through you every second, ghost-like, without you noticing and then continue on their way. (But don’t worry, like a friendly ghost, they don’t harm you!) Fermi traced the neutrino IceCube detected back to a supermassive black hole in a distant galaxy. By the time it reached Earth, it had traveled for 3.7 billion years at almost the speed of light!
Black Widow Pulsars
Black widows and redbacks are species of spiders with a reputation for devouring their partners. Astronomers have discovered two types of star systems that behave in a similar way. Sometimes when a star explodes as a supernova, it collapses back into a rapidly spinning, incredibly dense star called a pulsar. If there’s a lighter star nearby, it can get stuck in a close orbit with the pulsar, which blasts it with gamma rays, magnetic fields and intense winds of energetic particles. All these combine to blow clouds of material off the low-mass star. Eventually, the pulsar can eat away at its companion entirely.
Dark Matter
What’s scarier than a good unsolved mystery? Dark matter is a little-understood substance that makes up most of the matter in the universe. The stuff that we can see — stars, people, haunted houses, candy — is made up of normal matter. But our surveys of the cosmos tell us there’s not enough normal matter to keep things working the way they do. There must be another type of matter out there holding everything together. One of Fermi’s jobs is to help scientists narrow down the search for dark matter. Last year, researchers noticed that most of the gamma rays coming from the Andromeda galaxy are confined to its center instead of being spread throughout. One possible explanation is that accumulated dark matter at the center of the galaxy is emitting gamma rays!
Fermi has helped us learn a lot about the gamma-ray universe over the last 10 years. Learn more about its accomplishments and the other mysteries it’s working to solve. What other surprises are waiting out among the stars?
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10 Things: Mysterious 'Oumuamua
The interstellar object 'Oumuamua perplexed scientists in October 2017 as it whipped past Earth at an unusually high speed. This mysterious visitor is the first object ever seen in our solar system that is known to have originated elsewhere. Here are five things we know and five things we don’t know about the first confirmed interstellar object to pass through our solar system.
1. We know it’s not from around here.
The object known as 1I/2017 U1 (and nicknamed ‘Oumuamua) was traveling too fast (196,000 mph, that’s 54 miles per second or 87.3 kilometers per second) to have originated in our solar system. Comets and asteroids from within our solar system move at a slower speed, typically an average of 12 miles per second (19 kilometers per second) . In non-technical terms, 'Oumuamua is an “interstellar vagabond.”
Artist impression of the interstellar object ‘Oumuamua. Credit: ESA/Hubble, NASA, ESO, M. Kornmesser
2. We’re not sure where it came from.
'Oumuamua entered our solar system from the rough direction of the constellation Lyra, but it’s impossible to tell where it originally came from. Thousands of years ago, when 'Oumuamua started to wander from its parent planetary system, the stars were in a different position so it’s impossible to pinpoint its point of origin. It could have been wandering the galaxy for billions of years.
3. We know it’s out of here.
'Oumuamua is headed back out of our solar system and won’t be coming back. It’s rapidly headed in the direction of the constellation Pegasus and will cross the orbit of Neptune in about four years and cover one light year’s distance in about 11,000 years.
4. We don’t really know what it looks like.
We’ve only seen it as a speck of light through a telescope (it is far away and less than half a mile in length), but its unique rotation leads us to believe that it’s elongated like a cigar, about 10 times longer than it is wide. We can’t see it anymore. Artist’s concepts are the best guesses at what it might look like.
5. We know it got a little speed boost.
A rapid response observing campaign allowed us to watch as 'Oumuamua got an unexpected boost in speed. The acceleration slightly changed its course from earlier predictions.
“This additional subtle force on ′Oumuamua likely is caused by jets of gaseous material expelled from its surface,” said Davide Farnocchia of the Center for Near Earth Object Studies (CNEOS) at NASA’s Jet Propulsion Laboratory. “This same kind of outgassing affects the motion of many comets in our solar system.”
6. We know it’s tumbling.
Unusual variations in the comet’s brightness suggest it is rotating on more than one axis.
This illustration shows ‘Oumuamua racing toward the outskirts of our solar system. As the complex rotation of the object makes it difficult to determine the exact shape, there are many models of what it could look like. Credits: NASA/ESA/STScI
7. We don’t know what it’s made of.
Comets in our solar system kick off lots of dust and gas when they get close to the Sun, but 'Oumuamua did not, which led observers to consider defining it as an asteroid.
Karen Meech, an astronomer at the University of Hawaii’s Institute of Astronomy, said small dust grains, present on the surface of most comets, may have eroded away during ′Oumuamua's long journey through interstellar space. "The more we study ′Oumuamua, the more exciting it gets." she said. It could be giving off gases that are harder to see than dust, but it’s impossible to know at this point.
8. We knew to expect it.
Just not when. The discovery of an interstellar object has been anticipated for decades. The space between the stars probably has billions and billions of asteroids and comets roaming around independently. Scientists understood that inevitably, some of these small bodies would enter our own solar system. This interstellar visit by ‘Oumuamua reinforces our models of how planetary systems form.
9. We don’t know what it’s doing now.
After January 2018, 'Oumuamua was no longer visible to telescopes, even in space. But scientists continue to analyze the data gathered during the international observing campaign and crack open more mysteries about this unique interstellar visitor.
10. We know there’s a good chance we’ll see another one...eventually.
Because ′Oumuamua is the first interstellar object ever observed in our solar system, researchers caution that it’s difficult to draw general conclusions about this newly-discovered class of celestial bodies. Observations point to the possibility that other star systems regularly eject small comet-like objects and there should be more of them drifting among the stars. Future ground- and space-based surveys could detect more of these interstellar vagabonds, providing a larger sample for scientists to analyze. Adds, Karen Meech, an astronomer at the University of Hawaii’s Institute of Astronomy: “I can hardly wait for the next interstellar object!"
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What are the Universe’s Most Powerful Particle Accelerators?
Every second, every square meter of Earth’s atmosphere is pelted by thousands of high-energy particles traveling at nearly the speed of light. These zippy little assailants are called cosmic rays, and they’ve been puzzling scientists since they were first discovered in the early 1900s. One of the Fermi Gamma-ray Space Telescope’s top priority missions has been to figure out where they come from.
“Cosmic ray” is a bit of a misnomer. Makes you think they’re light, right? But they aren’t light at all! They’re particles that mostly come from outside our solar system — which means they're some of the only interstellar matter we can study — although the Sun also produces some. Cosmic rays hit our atmosphere and break down into secondary cosmic rays, most of which disperse quickly in the atmosphere, although a few do make it to Earth’s surface.
Cosmic rays aren't dangerous to those of us who spend our lives within Earth's atmosphere. But if you spend a lot of time in orbit or are thinking about traveling to Mars, you need to plan how to protect yourself from the radiation caused by cosmic rays.
Cosmic rays are subatomic particles — smaller particles that make up atoms. Most of them (99%) are nuclei of atoms like hydrogen and helium stripped of their electrons. The other 1% are lone electrons. When cosmic rays run into molecules in our atmosphere, they produce secondary cosmic rays, which include even lighter subatomic particles.
Most cosmic rays reach the same amount of energy a small particle accelerator could produce. But some zoom through the cosmos at energies 40 million times higher than particles created by the world’s most powerful man-made accelerator, the Large Hadron Collider. (Lightning is also a pretty good particle accelerator).
So where do cosmic rays come from? We should just be able to track them back to their source, right? Not exactly. Any time they run into a strong magnetic field on their way to Earth, they get deflected and bounce around like a game of cosmic pinball. So there’s no straight line to follow back to the source. Most of the cosmic rays from a single source don’t even make it to Earth for us to measure. They shoot off in a different direction while they’re pin balling.
Photo courtesy of Argonne National Laboratory
In 1949 Enrico Fermi — an Italian-American physicist, pioneer of high-energy physics and Fermi satellite namesake — suggested that cosmic rays might accelerate to their incredible speeds by ricocheting around inside the magnetic fields of interstellar gas clouds. And in 2013, the Fermi satellite showed that the expanding clouds of dust and gas produced by supernovas are a source of cosmic rays.
When a star explodes in a supernova, it produces a shock wave and rapidly expanding debris. Particles trapped by the supernova remnant magnetic field bounce around wildly.
Every now and then, they cross the shock wave and their energy ratchets up another notch. Eventually they become energetic enough to break free of the magnetic field and zip across space at nearly the speed of light — some of the fastest-traveling matter in the universe.
How can we track them back to supernovas when they don’t travel in a straight line, you ask? Very good question! We use something that does travel in a straight line — gamma rays (actual rays of light this time, on the more energetic end of the electromagnetic spectrum).
When the particles get across the shock wave, they interact with non-cosmic-ray particles in clouds of interstellar gas. Cosmic ray electrons produce gamma rays when they pass close to an atomic nucleus. Cosmic ray protons, on the other hand, produce gamma rays when they run into normal protons and produce another particle called a pion (Just hold on! We’re almost there!) which breaks down into two gamma rays.
The proton- and electron-produced gamma rays are slightly different. Fermi data taken over four years showed that most of the gamma rays coming from some supernova remnants have the energy signatures of cosmic ray protons knocking into normal protons. That means supernova remnants really are powerful particle accelerators, creating a lot of the cosmic rays that we see!
There are still other cosmic ray sources on the table — like active galactic nuclei — and Fermi continues to look for them. Learn more about what Fermi’s discovered over the last 10 years and how we’re celebrating its accomplishments.
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Our Most “Liked” Instagram Posts of 2017
Our Instagram page has over 2,200 images and is lucky enough to be followed by more than 29 million fans.
What images and videos were your favorite from this past year? Great question, and one we asked ourselves too!
Here’s a look at our most liked Instagram posts* of 2017…Enjoy!
#10 Black Hole Collision
What happens when two supermassive black holes collide? Until last year, we weren’t quite sure. Gravitational waves! With 834,169 likes, this image is our 10th most liked of 2017.
#9 Italy Through the Space Station Cupola Window
European astronaut Paolo Nespoli (@Astro_Paolo) shared this image on social media of "Southern #Italy and Sicily framed by one of our Cupola windows" aboard the International Space Station. This image ranks #9 for 2017 with 847,365 likes.
#8 Black Hole Friday
For our 5th annual #BlackHoleFriday we’ll share awesome images and facts about black holes! A black hole is a place in space where gravity pulls so much that even light cannot get out. With 916,247 likes, this picture ranks #8 for 2017.
#7 The Elements of Cassiopeia A
Did you know that stellar explosions and their remains--“supernova remnants”--are a source of chemical elements essential for life here on Earth? A new Chandra X-ray Observatory image captures the location of several vital elements like silicon (red), sulfur (yellow), calcium (green) and iron (purple), located on Cassiopeia A--a supernova remnant ~11,000 light years from Earth. This image ranks #7 for 2017 with 943,806 likes.
#6 Jupiter Blues
Jupiter, you’re bluetiful 💙 ! Churning swirls of Jupiter’s clouds are seen in striking shades of blue in this new view taken by our Juno spacecraft. This image ranks as our sixth most liked Instagram post of 2017 with 990,944 likes.
#5 An Interstellar Visitor
An interstellar visitor…scientists have confirmed that an intriguing asteroid that zipped through our solar system in October is the first confirmed object from another star! Observations suggest that this unusual object had been wandering through the Milky Way, unattached to any star system, for hundreds of millions of years before its chance encounter with our star system. With 1,015,721 likes, this image ranks #5 for 2017.
#4 Space Station Lunar Transit
Space station supermoon. This composite image made from six frames shows the International Space Station, with a crew of six onboard, as it transits the Moon at roughly five miles per second on Dec. 2. This image ranks #4 for 2017 with 1,037,520 likes.
#3 The Space Between Us
A post shared by NASA (@nasa) on Dec 20, 2017 at 2:56pm PST
The beautiful space between Earth and the International Space Station was immortalized by NASA astronaut Mark Vande Hei while orbiting 250 miles above the planet we call home. This majestic image ranks #3 for 2017 with 1,042,403 likes.
#2 The Moon Swallows the Sun
A post shared by NASA (@nasa) on Aug 21, 2017 at 2:03pm PDT
Today, the Sun disappeared, seemingly swallowed by our Moon–at least for a while. The August 21 solar eclipse cut through a swath of North America from coast to coast and those along the path of totality, that is where the Moon completely covered the Sun, were faced with a sight unseen in the U.S. in 99 years. Which might have something to do with this image ranking #2 for 2017 with 1,144,503 likes.
#1 Solar Eclipse Over Cascade Lake
A post shared by NASA (@nasa) on Aug 21, 2017 at 3:57pm PDT
Behold! This progression of the partial solar eclipse took place over Ross Lake, in Northern Cascades National Park, Washington on Monday, Aug. 21, 2017.
This photo was our #1 image of 2017 with 1,471,114 likes!
See them all here!
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*Posts and rankings are were taken as of Dec. 28, 2017.
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The twin Voyager spacecraft, which launched in 1977, are our ambassadors to the rest of the Milky Way, destined to continue orbiting the center of our galaxy for billions of years after they stop communicating with Earth. On Aug. 25, 2012, Voyager 1 became the first human-made object to enter interstellar space, and Voyager 2 is expected to cross over in the next few years. At age 40, the Voyagers are the farthest and longest-operating spacecraft and still have plenty more to discover. This poster captures the spirit of exploration, the vastness of space and the wonder that has fueled this ambitious journey to the outer planets and beyond.
Enjoy this and other Voyager anniversary posters. Download them for free here: https://voyager.jpl.nasa.gov/downloads/
Credit: NASA/JPL-Caltech
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Voyager: The Space Between
Our Voyager 1 spacecraft officially became the first human-made object to venture into interstellar space in 2012.
Whether and when our Voyager 1 spacecraft broke through to interstellar space, the space between stars, has been a thorny issue.
In 2012, claims surfaced every few months that Voyager 1 had “left our solar system.” Why had the Voyager team held off from saying the craft reached interstellar space until 2013?
Basically, the team needed more data on plasma, which is an ionozied gas that exists throughout space. (The glob of neon in a storefront sign is an example of plasma).
Plasma is the most important marker that distinguishes whether Voyager 1 is inside the solar bubble, known as the heliosphere. The heliosphere is defined by the constant stream of plasma that flows outward from our Sun – until it meets the boundary of interstellar space, which contains plasma from other sources.
Adding to the challenge: they didn’t know how they’d be able to detect it.
No one has been to interstellar space before, so it’s like traveling with guidebooks that are incomplete.
Additionally, Voyager 1’s plasma instrument, which measures the density, temperature and speed of plasma, stopped working in 1980, right after its last planetary flyby.
When Voyager 1 detected the pressure of interstellar space on our heliosphere in 2004, the science team didn’t have the instrument that would provide the most direct measurements of plasma.
Voyager 1 Trajectory
Instead, they focused on the direction of the magnetic field as a proxy for source of the plasma. Since solar plasma carries the magnetic field lines emanating from the Sun and interstellar plasma carries interstellar magnetic field lines, the directions of the solar and interstellar magnetic fields were expected to differ.
Voyager 2 Trajectory
In May 2012, the number of galactic cosmic rays made its first significant jump, while some of the inside particles made their first significant dip. The pace of change quickened dramatically on July 28, 2012. After five days, the intensities returned to what they had been. This was the first taste test of a new region, and at the time Voyager scientists thought the spacecraft might have briefly touched the edge of interstellar space.
By Aug. 25, when, as we now know, Voyager 1 entered this new region for good, all the lower-energy particles from inside zipped away. Some inside particles dropped by more than a factor of 1,000 compared to 2004. However, subsequent analysis of the magnetic field data revealed that even though the magnetic field strength jumped by 60% at the boundary, the direction changed less than 2 degrees. This suggested that Voyager 1 had not left the solar magnetic field and had only entered a new region, still inside our solar bubble, that had been depleted of inside particles.
Then, in April 2013, scientists got another piece of the puzzle by chance. For the first eight years of exploring the heliosheath, which is the outer layer of the heliosphere, Voyager’s plasma wave instrument had heard nothing. But the plasma wave science team had observed bursts of radio waves in 1983 and 1984 and again in 1992 and 1993. They determined these bursts were produced by the interstellar plasma when a large outburst of solar material would plow into it and cause it to oscillate.
It took about 400 days for such solar outbursts to reach interstellar space, leading to an estimated distance of 117 to 177 AU (117 to 177 times the distance from the Sun to the Earth) to the heliopause.
Then on April 9, 2013, it happened: Voyager 1’s plasma wave instrument picked up local plasma oscillations. Scientists think they probably stemmed from a burst of solar activity from a year before. The oscillations increased in pitch through May 22 and indicated that Voyager was moving into an increasingly dense region of plasma.
The above soundtrack reproduces the amplitude and frequency of the plasma waves as “heard” by Voyager 1. The waves detected by the instrument antennas can be simply amplified and played through a speaker. These frequencies are within the range heard by human ears.
When they extrapolated back, they deduced that Voyager had first encountered this dense interstellar plasma in Aug. 2012, consistent with the sharp boundaries in the charged particle and magnetic field data on Aug. 25.
In the end, there was general agreement that Voyager 1 was indeed outside in interstellar space, but that location comes with some disclaimers. They determined the spacecraft is in a mixed transitional region of interstellar space. We don’t know when it will reach interstellar space free from the influence of our solar bubble.
Voyager 1, which is working with a finite power supply, has enough electrical power to keep operating the fields and particles science instruments through at least 2020, which will make 43 years of continual operation.
Voyager 1 will continue sending engineering data for a few more years after the last science instrument is turned off, but after that it will be sailing on as a silent ambassador.
In about 40,000 years, it will be closer to the star AC +79 3888 than our own Sun.
And for the rest of time, Voyager 1 will continue orbiting around the heart of the Milky Way galaxy, with our Sun but a tiny point of light among many.
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