Black Hole Image Makes History; NASA Telescopes Coordinated Observations
A black hole and its shadow have been captured in an image for the first time, a historic feat by an international network of radio telescopes called the Event Horizon Telescope (EHT). EHT is an international collaboration whose support in the U.S. includes the National Science Foundation.
A black hole is an extremely dense object from which no light can escape. Anything that comes within a black hole’s “event horizon,” its point of no return, will be consumed, never to re-emerge, because of the black hole’s unimaginably strong gravity. By its very nature, a black hole cannot be seen, but the hot disk of material that encircles it shines bright. Against a bright backdrop, such as this disk, a black hole appears to cast a shadow.
The stunning new image shows the shadow of the supermassive black hole in the center of Messier 87 (M87), an elliptical galaxy some 55 million light-years from Earth. This black hole is 6.5 billion times the mass of the Sun. Catching its shadow involved eight ground-based radio telescopes around the globe, operating together as if they were one telescope the size of our entire planet.
“This is an amazing accomplishment by the EHT team,” said Paul Hertz, director of the astrophysics division at NASA Headquarters in Washington. “Years ago, we thought we would have to build a very large space telescope to image a black hole. By getting radio telescopes around the world to work in concert like one instrument, the EHT team achieved this, decades ahead of time.”
To complement the EHT findings, several NASA spacecraft were part of a large effort, coordinated by the EHT’s Multiwavelength Working Group, to observe the black hole using different wavelengths of light. As part of this effort, NASA’s Chandra X-ray Observatory, Nuclear Spectroscopic Telescope Array (NuSTAR) and Neil Gehrels SwiftObservatory space telescope missions, all attuned to different varieties of X-ray light, turned their gaze to the M87 black hole around the same time as the Event Horizon Telescope in April 2017. If EHT observed changes in the structure of the black hole’s environment, data from these missions and other telescopes could be used to help figure out what was going on.
While NASA observations did not directly trace out the historic image, astronomers used data from NASA’s Chandra and NuSTAR satellites to measure the X-ray brightness of M87’s jet. Scientists used this information to compare their models of the jet and disk around the black hole with the EHT observations. Other insights may come as researchers continue to pore over these data.
There are many remaining questions about black holes that the coordinated NASA observations may help answer. Mysteries linger about why particles get such a huge energy boost around black holes, forming dramatic jets that surge away from the poles of black holes at nearly the speed of light. When material falls into the black hole, where does the energy go?
“X-rays help us connect what’s happening to the particles near the event horizon with what we can measure with our telescopes,” said Joey Neilsen, an astronomer at Villanova University in Pennsylvania, who led the Chandra and NuSTAR analysis on behalf of the EHT’s Multiwavelength Working Group.
NASA space telescopes have previously studied a jet extending more than 1,000 light-years away from the center of M87. The jet is made of particles traveling near the speed of light, shooting out at high energies from close to the event horizon. The EHT was designed in part to study the origin of this jet and others like it. A blob of matter in the jet called HST-1, discovered by Hubble astronomers in 1999, has undergone a mysterious cycle of brightening and dimming.
Chandra, NuSTAR and Swift, as well as NASA’s Neutron star Interior Composition Explorer (NICER) experiment on the International Space Station, also looked at the black hole at the center of our own Milky Way galaxy, called Sagittarius A*, in coordination with EHT.
Getting so many different telescopes on the ground and in space to all look toward the same celestial object is a huge undertaking in and of itself, scientists emphasize.
“Scheduling all of these coordinated observations was a really hard problem for both the EHT and the Chandra and NuSTAR mission planners,” Neilsen said. “They did really incredible work to get us the data that we have, and we’re exceedingly grateful.”
Neilsen and colleagues who were part of the coordinated observations will be working on dissecting the entire spectrum of light coming from the M87 black hole, all the way from low-energy radio waves to high-energy gamma rays. With so much data from EHT and other telescopes, scientists may have years of discoveries ahead.
Original article:
http://nasa.gov/mission_pages/chandra/news/black-hole-image-makes-history
Time And Space
the fact that jupiter and saturn haven’t been physically and observably this close since 1226 is so poetic bc you’re telling me i’m going to look up at and admire the same astronomical anomaly in the sky that someone hundreds and hundreds of years ago, with less knowledge of the stars and the planets than we have now, also looked up at and admired nonetheless. the past is long gone but the awareness of being connected to someone somewhere long ago thru the night sky is overwhelming me
So you know those mutant strains of radiotrophic fungus they discovered in Chernobyl? The ones that feed on gamma radiation? Those fungi, the radiation-eating fungi? From Chernobyl? They brought some on board the International Space Station and took some measurements. Here is the paper, titled:
Space is full of high-energy radiation, and radiation shielding is a big engineering challenge for Martian habitats and deep-space missions. What they figured out is that an 8-inch thick layer of mutant Chernobyl radiation-eating fungus in the walls of the spacecraft or habitat would serve as a self-replicating, self-sustaining radiation shield for long-haul missions.
This sounds like such a good and normal idea! Let’s do it!
Welcome to our 6th annual annual Black Hole Friday! Check out these black hole deals from the past year as you prepare to head out for a shopping spree or hunker down at home to avoid the crowds.
First things first, black holes have one basic rule: They are so incredibly dense that to escape their surface you’d have to travel faster than light. But light speed is the cosmic speed limit … so nothing can escape a black hole’s surface!
Some black holes form when a very large star dies in a supernova explosion and collapses into a superdense object. This is even more jam-packed than the crowds at your local mall — imagine an object 10 times more massive than the Sun squeezed into a sphere with the diameter of New York City!
Some of these collapsing stars also signal their destruction with a huge burst of gamma rays. Our Fermi Gamma-ray Space Telescope and Neil Gehrels Swift Observatory continuously seek out the signals of these gamma ray bursts — black hole birth announcements that come to us from across the universe.
There are loads of stellar mass black holes, which are just a few 10s of times the Sun’s mass, in our home galaxy alone — maybe even hundreds of millions of them! Our Neutron Star Interior Composition Explorer, or NICER for short, experiment on the International Space Station has been studying some of those relatively nearby black holes.
Near one black hole called GRS 1915+105, NICER found disk winds — fast streams of gas created by heat or pressure. Scientists are still figuring out some puzzles about these types of wind. Where do they come from, for example? And do they change the way material falls into the black hole? Every new example of these disk winds helps astronomers get closer to answering those questions.
But stellar mass black holes aren’t the only ones out there. At the center of nearly every large galaxy lies a supermassive black hole — one with the mass of millions or billions of Suns smooshed into a region no bigger than our solar system.
There’s still some debate about how these monsters form, but astronomers agree that they certainly can collide and combine when their host galaxies collide and combine. Those black holes will have a lot of gas and dust around them. As that material is pulled into the black hole it will heat up due to friction and other forces, causing it to emit light. A group of scientists wondered what light it would produce and created this mesmerizing visualization showing that most of the light produced around these two black holes is UV or X-ray light. We can’t see those wavelengths with our own eyes, but many telescopes can. Models like this could help scientists know what to look for to spot a merger.
It also turns out that these supermassive black holes are the source of some of the brightest objects in the gamma ray sky! In a type of galaxy called active galactic nuclei (also called “AGN” for short) the central black hole is surrounded by a disk of gas and dust that’s constantly falling into the black hole.
But not only that, some of those AGN have jets of energetic particles that are shooting out from near the black hole at nearly the speed of light! Scientists are studying these jets to try to understand how black holes — which pull everything in with their huge amounts of gravity — provide the energy needed to propel the particles in these jets. If that jet is pointed directly at us, it can appear super-bright in gamma rays and we call it a blazar. These blazars make up more than half of the sources our Fermi space telescope sees.
Sometimes scientists get a two-for-one kind of deal when they’re looking for black holes. Our colleagues at the IceCube Neutrino Observatory actually caught a particle from a blazar 4 billion light-years away. IceCube lies a mile under the ice in Antarctica and uses the ice itself to detect neutrinos, tiny speedy particles that weigh almost nothing and rarely interact with anything. When IceCube caught a super-high-energy neutrino and traced its origin to a specific area of the sky, they turned to the astronomical community to pinpoint the source.
Our Fermi spacecraft scans the entire sky about every three hours and for months it had observed a blazar producing more gamma rays than usual. Flaring is a common characteristic in blazars, so this didn’t attract special attention. But when the alert from IceCube came through, scientists realized the neutrino and the gamma rays came from the same patch of sky! This method of using two or more kinds of signals to learn about one event or object is called multimessenger astronomy, and it’s helping us learn a lot about the universe.
Get more fun facts and information about black holes HERE and follow us on social media today for other cool facts and findings about black holes!
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Thirty years ago, archeologists excavated the tomb of an elite 40-50-year-old man from the Sicán culture of Peru, a society that predated the Incas. The man’s seated, upside-down skeleton was painted bright red, as was the gold mask covering his detached skull. Now, researchers reporting in ACS’ Journal of Proteome Research have analyzed the paint, finding that, in addition to a red pigment, it contains human blood and bird egg proteins.
The Sicán was a prominent culture that existed from the ninth to 14th centuries along the northern coast of modern Peru. During the Middle Sicán Period (about 900–1,100 A.D.), metallurgists produced a dazzling array of gold objects, many of which were buried in tombs of the elite class. In the early 1990s, a team of archaeologists and conservators led by Izumi Shimada excavated a tomb where an elite man’s seated skeleton was painted red and placed upside down at the center of the chamber. Read more.
The recent detection of two neutron stars colliding has sent waves through spacetime and the astronomical community.
You may have seen headlines in the news and not really know why this is such a big deal.
Here’s the Sparknotes version:
A while back a thing called “gravitational waves” were observed for the first time. These are fluctuations in the fabric of spacetime that propagate out from their source just like light, i.e. radially/like a pebble dropped in water. General relativity shows us that the acceleration of objects with mass cause this event to occur.
Until fairly recently these have been too difficult to observe and in fact Einstein didn’t think we’d ever be able to. A series of laser interferometers have disproved that assumption. Using high-precision analysis of how the lasers shift as a gravitational wave moves through them scientists can now see the small movements in the universe that are gravitational waves.
Importantly, we now have three such observatories capable of working together. Known as the “LIGO-Virgo” team, two observatories in the U.S. and one in Italy detected these shifting in spacetime. Three is a pretty magical number in coordinating detections like this because you can then triangulate where the signal comes from and…
BINGO! Within hours optical observatories were zeroing in on the predicted source of these spacetime fluctuations. Indeed, they confirmed the presence of a previously unseen glow:
What you’re looking at is the glow of two neutron stars colliding into each other. This explosion has the energy of approximately 260,000,000 suns.
Each of these stars has such a large mass that the waves in spacetime are actually detectable from a distance of 140 million light-years away.
Impressive, right? Although you might agree, this still begs the question of what exactly we’ve learned from this event. Well - a lot. Since this is the first observation we have made with both gravitational wave observatories and more traditional astronomical observatories (i.e. light detecting ones) we’ve been able to put some numbers on the phenomenon. Here are some of the things we’ve learned:
1) Gravitational waves propagate at the speed of light!
2) A huge portion of heavier elements (like gold and uranium!) may have their origins in neutron star collisions! Nuclear synthesis in stars more typical like the sun is restricted to closer to 10% of the star’s mass being able to fuse elements together into new ones. This process is actually quite inefficient (actually, YOU are a more efficient radiator than the sun!) and it becomes more difficult for a star to fuse the heavier elements. Before this event we didn’t have a good way of explaining why we found so much more heavy stuff than stellar nuclear synthesis could account for. Now? Baboom! This neutron star collision resulted in the synthesis of so much gold that it’s about 150 times more massive than the Earth! Cha-Ching!
So if you’re an amateur (or professional, I suppose) astronomer and you want to see this collision, now dubbed GW170817, and you build a little radio telescope (another post!), you’ll be able to detect this collision for the next 5-10 years due to the afterglow.
(Image credit: NASA and ESA)
Neutron stars are probably one of the weirdest type of objects to exist in the universe… but first let me explain what a neutron star is
when a star with the mass of 8-20 times of the sun dies (and by dies I mean fucking explodes), the core collapses to form a neutron star
they are incredibly dense, spin rapidly and have very strong magnetic fields
sounds all fun and games, right? sounds normal? well listen up
So, we know that electrons usually refuse to be squeezed together. but in a death event of a big star, the pressure is so extreme that protons and electrons get violently SMASHED together and form neutrons.
sounds like someone needs to take an anti-agression class if you ask me
Now, what once was a star more massive than the Sun, is condensed to a tiny ball (usually about 10-20km!) of neutrons, with all of the mass in this tiny ball.
To visualize, imagine the mass of the Sun (300 000X the mass of the Earth), in a little 20km sphere, the size of a small city.
To visualize the density of a neutron star, think of the classic model of the atom. if an atom was a sports field 100m across, it would be mostly empty. almost all of the atom’s mass sits in the core, in this example, the core is the size of a marble.
but in a neutron star, this doesn’t apply anymore. in a neutron star, the entire stadium would be filled to the brim with neutrons. ALL. OF. IT.
a single cubic centimetre of Neutronium has the mass of 400 million tons. that’s the total mass of every single car and truck in the US.
the typical gravity of a neutron star is about 100 million times of that of the Earth. clingy as shit
so far, we have detected over 1000 of these weird fucks in our galaxy alone. yikes
some Neutron stars are vampires. They can be in a binary star system where a normal star orbits them and they feed of that material
summary: extremely weird and violent space ball of rage, tiny, filled to the top with anger, sometimes a vampire
by Stephen Messenger
“For thousands of years, Judean date palm trees were one of the most recognizable and welcome sights for people living in the Middle East — widely cultivated throughout the region for their sweet fruit, and for the cool shade they offered from the blazing desert sun.
From its founding some 3,000 years ago, to the dawn of the Common Era, the trees became a staple crop in the Kingdom of Judea, even garnering several shout-outs in the Old Testament. Judean palm trees would come to serve as one of the kingdom’s chief symbols of good fortune; King David named his daughter, Tamar, after the plant’s name in Hebrew.
By the time the Roman Empire sought to usurp control of the kingdom in 70 AD, broad forests of these trees flourished as a staple crop to the Judean economy — a fact that made them a prime resource for the invading army to destroy. Sadly, around the year 500 AD, the once plentiful palm had been completely wiped out, driven to extinction for the sake of conquest.
In the centuries that followed, first-hand knowledge of the tree slipped from memory to legend. Up until recently, that is.
During excavations at the site of Herod the Great’s palace in Israel in the early 1960’s, archeologists unearthed a small stockpile of seeds stowed in a clay jar dating back 2,000 years. For the next four decades, the ancient seeds were kept in a drawer at Tel Aviv’s Bar-Ilan University. But then, in 2005, botanical researcher Elaine Solowey decided to plant one and see what, if anything, would sprout.
“I assumed the food in the seed would be no good after all that time. How could it be?“ said Solowey. She was soon proven wrong.
Amazingly, the multi-millennial seed did indeed sprout — producing a sapling no one had seen in centuries, becoming the oldest known tree seed to germinate.
Today, the living archeological treasure continues to grow and thrive; In 2011, it even produced its first flower — a heartening sign that the ancient survivor was eager to reproduce. It has been proposed that the tree be cross-bred with closely related palm types, but it would likely take years for it to begin producing any of its famed fruits. Meanwhile, Solowey is working to revive other age-old trees from their long dormancy.”
***Does anyone in the know have any comments?
(Source: Tree Hugger)
We’re learning more every day about black holes thanks to one of the instruments aboard the International Space Station! Our Neutron star Interior Composition Explorer (NICER) instrument is keeping an eye on some of the most mysterious cosmic phenomena.
We’re going to talk about some of the amazing new things NICER is showing us about black holes. But first, let’s talk about black holes — how do they work, and where do they come from? There are two important types of black holes we’ll talk about here: stellar and supermassive. Stellar mass black holes are three to dozens of times as massive as our Sun while supermassive black holes can be billions of times as massive!
Stellar black holes begin with a bang — literally! They are one of the possible objects left over after a large star dies in a supernova explosion. Scientists think there are as many as a billion stellar mass black holes in our Milky Way galaxy alone!
Supermassive black holes have remained rather mysterious in comparison. Data suggest that supermassive black holes could be created when multiple black holes merge and make a bigger one. Or that these black holes formed during the early stages of galaxy formation, born when massive clouds of gas collapsed billions of years ago. There is very strong evidence that a supermassive black hole lies at the center of all large galaxies, as in our Milky Way.
Imagine an object 10 times more massive than the Sun squeezed into a sphere approximately the diameter of New York City — or cramming a billion trillion people into a car! These two examples give a sense of how incredibly compact and dense black holes can be.
Because so much stuff is squished into such a relatively small volume, a black hole’s gravity is strong enough that nothing — not even light — can escape from it. But if light can’t escape a dark fate when it encounters a black hole, how can we “see” black holes?
Scientists can’t observe black holes directly, because light can’t escape to bring us information about what’s going on inside them. Instead, they detect the presence of black holes indirectly — by looking for their effects on the cosmic objects around them. We see stars orbiting something massive but invisible to our telescopes, or even disappearing entirely!
When a star approaches a black hole’s event horizon — the point of no return — it’s torn apart. A technical term for this is “spaghettification” — we’re not kidding! Cosmic objects that go through the process of spaghettification become vertically stretched and horizontally compressed into thin, long shapes like noodles.
Scientists can also look for accretion disks when searching for black holes. These disks are relatively flat sheets of gas and dust that surround a cosmic object such as a star or black hole. The material in the disk swirls around and around, until it falls into the black hole. And because of the friction created by the constant movement, the material becomes super hot and emits light, including X-rays.
At last — light! Different wavelengths of light coming from accretion disks are something we can see with our instruments. This reveals important information about black holes, even though we can’t see them directly.
So what has NICER helped us learn about black holes? One of the objects this instrument has studied during its time aboard the International Space Station is the ever-so-forgettably-named black hole GRS 1915+105, which lies nearly 36,000 light-years — or 200 million billion miles — away, in the direction of the constellation Aquila.
Scientists have found disk winds — fast streams of gas created by heat or pressure — near this black hole. Disk winds are pretty peculiar, and we still have a lot of questions about them. Where do they come from? And do they change the shape of the accretion disk?
It’s been difficult to answer these questions, but NICER is more sensitive than previous missions designed to return similar science data. Plus NICER often looks at GRS 1915+105 so it can see changes over time.
NICER’s observations of GRS 1915+105 have provided astronomers a prime example of disk wind patterns, allowing scientists to construct models that can help us better understand how accretion disks and their outflows around black holes work.
NICER has also collected data on a stellar mass black hole with another long name — MAXI J1535-571 (we can call it J1535 for short) — adding to information provided by NuSTAR, Chandra, and MAXI. Even though these are all X-ray detectors, their observations tell us something slightly different about J1535, complementing each other’s data!
This rapidly spinning black hole is part of a binary system, slurping material off its partner, a star. A thin halo of hot gas above the disk illuminates the accretion disk and causes it to glow in X-ray light, which reveals still more information about the shape, temperature, and even the chemical content of the disk. And it turns out that J1535’s disk may be warped!
Image courtesy of NRAO/AUI and Artist: John Kagaya (Hoshi No Techou)
This isn’t the first time we have seen evidence for a warped disk, but J1535’s disk can help us learn more about stellar black holes in binary systems, such as how they feed off their companions and how the accretion disks around black holes are structured.
NICER primarily studies neutron stars — it’s in the name! These are lighter-weight relatives of black holes that can be formed when stars explode. But NICER is also changing what we know about many types of X-ray sources. Thanks to NICER’s efforts, we are one step closer to a complete picture of black holes. And hey, that’s pretty nice!
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On the night of May 26, 2010, the Stratospheric Observatory for Infrared Astronomy, or SOFIA, the world’s largest flying observatory, first peered into the cosmos. Its mission: to study celestial objects and astronomical phenomena with infrared light. Many objects in space emit almost all their energy at infrared wavelengths. Often, they are invisible when observed in ordinary, visible light. Over the last decade, the aircraft’s 106-inch telescope has been used to study black holes, planets, galaxies, star-forming nebulas and more! The observations have led to major breakthroughs in astronomy, revolutionizing our understanding of the solar system and beyond. To celebrate its 10 years of exploration, here’s a look at the top 10 discoveries made by our telescope on a plane:
Scientists believe that around 100,000 years after the big bang, helium and hydrogen combined to make a molecule called helium hydride. Its recent discovery confirms a key part of our basic understanding of the early universe.
More than a pretty picture, this panorama of cosmic scale reveals details that can help explain how massive stars are born and what’s feeding our Milky Way galaxy’s supermassive black hole.
A double-star system that is more than 300 light-years away likely had an extreme collision between two of its rocky planets. A similar event in our own solar system may have formed our Moon.
Fear not, the dark, my friend. And let the feast begin! Magnetic fields in the Cygnus A galaxy are trapping material where it is close enough to be devoured by a hungry black hole.
The planetary system around Epsilon Eridani, a star located about 10 light-years away, has an architecture remarkably similar to our solar system. What’s more, its central star is a younger, fainter version of our Sun.
Black holes in many galaxies are actively consuming material, but our Milky Way galaxy’s central black hole is relatively quiet. Observations show magnetic fields may be directing material around, not into, the belly of the beast.
Ever wonder how material leaves a galaxy? The wind flowing from the center of the Cigar Galaxy is so strong it’s pulling a magnetic field — and the mass of 50 to 60 million Suns — with it.
What happens when a star goes boom? It turns out that supernova explosions can produce a substantial amount of material from which planets like Earth can form.
They say siblings need time and space to grow, but here’s one that really needs some room. A newborn star in the Orion Nebula is clearing a bubble of space around it, preventing any new luminous family members from forming nearby.
Radiation from stars is making organic molecules in nebula NGC 7023, also known as the Iris Nebula, larger and more complex. The growth of these molecules is one of the steps that could lead to the emergence of life under the right circumstances.
SOFIA is a modified Boeing 747SP aircraft that allows astronomers to study the solar system and beyond in ways that are not possible with ground-based telescopes. Find out more about the mission at www.nasa.gov/SOFIA.
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