Black Hole Week

This gallery brings together resources related to NASA’s Black Hole Week — videos, social media products, news stories, still images, and assets. This week is a celebration of celestial objects with gravity so intense that even light cannot escape them. Our goal is that no matter where people turn that week they will run into a black hole. (Figuratively, of course — we don’t want anyone falling in!)

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Traveler Videos

The Traveler is our adventurous friend with a boundless enthusiasm for exploring the universe. A helpful narrator shares tips to keep them safe. Check out these videos to learn alongside the Traveler.
  • NASA's Guide To Black Hole Safety
    2019.09.23
    Have you ever thought about visiting a black hole? We sure hope not. However, if you're absolutely convinced that a black hole is your ideal vacation spot, watch this video before you blast off to learn more about them and (more importantly) how to stay safe. You can also download a handy safety brochure, watch short clips to learn different things about black holes, and even get some short glimpses into the lives of black holes and the explorers that want to visit them.
  • NASA's Field Guide to Black Holes - Episode 1: Basic Black Holes
    2021.04.12
    Thinking about doing some black hole watching the next time you’re on an intergalactic vacation, but you’re not quite sure where to start? Well, look no further! This series of videos shows you everything you need to know. With topics ranging from basic black holes, to fancy black holes, to giant black holes and their companions, you’ll be more than ready for your next adventure. In addition to the videos, you can also download a printable guide that has even more information. Note: While these videos can be shared in their entirety without permission, their music has been licensed and may not be excised or remixed in other products.
  • NASA's Field Guide to Black Holes- Episode 2: Fancy Black Holes
    2021.04.12
    Thinking about doing some black hole watching the next time you’re on an intergalactic vacation, but you’re not quite sure where to start? Well, look no further! This series of videos shows you everything you need to know. With topics ranging from basic black holes, to fancy black holes, to giant black holes and their companions, you’ll be more than ready for your next adventure. In addition to the videos, you can also download a printable guide that has even more information. Note: While these videos can be shared in their entirety without permission, their music has been licensed and may not be excised or remixed in other products.
  • NASA's Field Guide to Black Holes - Episode 3: Social Black Holes
    2021.04.12
    Thinking about doing some black hole watching the next time you’re on an intergalactic vacation, but you’re not quite sure where to start? Well, look no further! This series of videos shows you everything you need to know. With topics ranging from basic black holes, to fancy black holes, to giant black holes and their companions, you’ll be more than ready for your next adventure. In addition to the videos, you can also download a printable guide that has even more information. Note: While these videos can be shared in their entirety without permission, their music has been licensed and may not be excised or remixed in other products.
  • NASA's Field Guide to Black Holes - Episode 4: Social Supermassive Black Holes
    2021.04.12
    Thinking about doing some black hole watching the next time you’re on an intergalactic vacation, but you’re not quite sure where to start? Well, look no further! This series of videos shows you everything you need to know. With topics ranging from basic black holes, to fancy black holes, to giant black holes and their companions, you’ll be more than ready for your next adventure. In addition to the videos, you can also download a printable guide that has even more information. Note: While these videos can be shared in their entirety without permission, their music has been licensed and may not be excised or remixed in other products.
  • NASA's Field Guide to Black Holes - Episode 5: Black Hole Records
    2021.04.12
    Thinking about doing some black hole watching the next time you’re on an intergalactic vacation, but you’re not quite sure where to start? Well, look no further! This series of videos shows you everything you need to know. With topics ranging from basic black holes, to fancy black holes, to giant black holes and their companions, you’ll be more than ready for your next adventure. In addition to the videos, you can also download a printable guide that has even more information. Note: While these videos can be shared in their entirety without permission, their music has been licensed and may not be excised or remixed in other products.

Other Traveler Media

In addition to videos, the Traveler and their friends are featured in a number of other multimedia resources. Check out these items which include safety and field guides, postcards, and wallpaper.
  • Black Hole Week Assets
    2022.02.28
    This page will introduce you to the world, characters, colors, and fonts of Black Hole Week. NASA celebrated Black Hole Week in 2019 and 2021, with the next installment planned for May 2-6, 2022. The world of Black Hole Week is bold, colorful, and a bit retro. It's also populated by a fun bunch of characters, including a little blue explorer (called the "Traveler") and their black hole friends. Below, you'll find tons of helpful images, GIFs, and other materials to get you going if you want to join in!
  • Black Hole Week: Traveler and Friends GIFs
    2022.04.12
    Black Hole Week, May 2-6, 2022 This page provides social media assets used during previous celebrations of Black Hole Week. The next installment is planned for May 2-6, 2022. The world of Black Hole Week is populated by a fun bunch of characters, including a little blue explorer (called the Traveler) and their cosmic friends. Below, you'll find tons of GIFs to download and use if you want to join in!
  • NASA's Field Guide to Black Holes - Printable Guide
    2021.04.12
    Thinking about doing some black hole watching the next time you’re on an intergalactic vacation, but you’re not quite sure where to start? Well, look no further! This series of videos shows you everything you need to know. With topics ranging from basic black holes, to fancy black holes, to giant black holes and their companions, you’ll be more than ready for your next adventure. In addition to the videos, you can also download a printable guide that has even more information. Note: While these videos can be shared in their entirety without permission, their music has been licensed and may not be excised or remixed in other products.
  • NASA's Guide To Black Hole Safety - Safety Brochure
    2019.09.23
    Have you ever thought about visiting a black hole? We sure hope not. However, if you're absolutely convinced that a black hole is your ideal vacation spot, watch this video before you blast off to learn more about them and (more importantly) how to stay safe. You can also download a handy safety brochure, watch short clips to learn different things about black holes, and even get some short glimpses into the lives of black holes and the explorers that want to visit them.
  • Black Hole Safety: Desktop & Phone Wallpaper
    2019.09.25
    So you’ve planned your trip to a black hole, you’ve packed your bags, and you’ve even watched the pre-flight safety video. If you haven’t yet watched the video, however, we highly recommend you click the image below. Don’t worry, we’ll wait. NASA's Guide To Black Hole Safety Now then, want to make black hole travel an even bigger part of your daily life? Wishing that black holes actually WERE portals to dimensions filled with unicorns and space potatoes? Download these phone and desktop wallpapers to fill your screens.
  • Black Hole Travel Postcards
    2019.09.23
    Wish you were here! Now, you can send your friends postcards from one of the most extreme vacation spots in the universe—or at least convince them you've gone even though you stayed safe at home.

Black Hole Visualizations

Since we can’t visit a black hole, visualizations allow us to see aspects of their complex physics at work. Check out the weird and wonderful things we’ve learned using supercomputers and complicated algorithms.
  • Black Hole Week Black Hole Gifs
    2022.04.12
    Black Hole Week, May 2-6, 2022 This page provides social media assets used during previous celebrations of Black Hole Week. The next installment is planned for May 2-6, 2022. Join in! Below, you'll find many GIFs to use.
  • Black Hole Desktop & Phone Wallpapers
    2022.05.04
    While black holes can’t emit their own light, matter surrounding and falling toward it can create quite a light show. Here you’ll find a collection of data visualizations, illustrations, and telescope images of black hole environments. Download these phone and desktop wallpapers for your screens.
  • NASA's Black Hole Orrery
    2022.05.02
    This visualization shows 22 X-ray binaries in our Milky Way galaxy and its nearest neighbor, the Large Magellanic Cloud, that host confirmed stellar-mass black holes. The systems are shown at the same physical scale, and their orbital motion is sped up by nearly 22,000 times. The view of each binary replicates how we see it from Earth. The star colors range from blue-white to reddish, representing temperatures from 5 times hotter to 45% cooler than our Sun. While the black holes appear on a scale reflecting their masses, all are depicted using spheres larger than actual size. Cygnus X-1, with the largest companion star shown, is the first black hole ever confirmed and weighs about 21 times more than the Sun. But its surface – called its event horizon – spans only about 77 miles (124 kilometers). The enlarged spheres also cover up visible distortions produced by the black holes’ gravitational effects. In most of these systems, a stream of gas flows directly from the star toward the black hole, forming around it a broad, flattened structure called an accretion disk. In others, like Cygnus X-1, a massive star produces a thick outflow called a stellar wind, some of which becomes swept up by the black hole’s intense gravity. Gas in the accretion disk heats up as the material slowly spirals inward, glowing in visible, ultraviolet, and finally X-ray light. Because the accretion disks reach even higher temperatures than the stars, they use a different color scheme.
  • Supercomputer Simulations Test Star-destroying Black Holes
    2021.11.26
    Watch as eight stars skirt a black hole 1 million times the mass of the Sun in these supercomputer simulations. As they approach, all are stretched and deformed by the black hole’s gravity. Some are completely pulled apart into a long stream of gas, a cataclysmic phenomenon called a tidal disruption event. Others are only partially disrupted, retaining some of their mass and returning to their normal shapes after their horrific encounters.

    These simulations are the first to combine the physical effects of Einstein’s general theory of relativity with realistic stellar density models. The virtual stars range from about one-tenth to 10 times the Sun’s mass.

    The division between stars that fully disrupt and those that endure isn’t simply related to mass. Instead, survival depends more on the star’s density.

    Scientists investigated how other characteristics, such as different black hole masses and stellar close approaches, affect tidal disruption events. The results will help astronomers estimate how often full tidal disruptions occur in the universe and will aid them in building more accurate pictures of these calamitous cosmic occurrences.

  • NASA Visualization Probes the Doubly Warped World of Binary Black Holes
    2021.04.15
    A pair of orbiting black holes millions of times the Sun’s mass perform a hypnotic dance in this NASA visualization. The movie traces how the black holes distort and redirect light emanating from the maelstrom of hot gas – called an accretion disk – that surrounds each one. Viewed from near the orbital plane, each accretion disk takes on a characteristic warped look. But as one passes in front of the other, the gravity of the foreground black hole transforms its partner into a rapidly changing sequence of arcs. These distortions play out as light from the accretion disks navigates the tangled fabric of space and time near the black holes. The simulated binary contains two supermassive black holes, a larger one with 200 million solar masses and a smaller companion weighing half as much. Astronomers think that in binary systems like this, both black holes could maintain accretion disks for millions of years. The disks have different colors, red and blue, to make it easier to track the light sources, but the choice also reflects reality. Gas orbiting lower-mass black holes experiences stronger effects that produce higher temperatures. For these masses, both accretion disks would actually emit most of their light in the UV, with the blue disk reaching a slightly higher temperature. Visualizations like this help scientists picture the fascinating consequences of extreme gravity’s funhouse mirror. Seen nearly edgewise, the accretion disks look noticeably brighter on one side. Gravitational distortion alters the paths of light coming from different parts of the disks, producing the warped image. The rapid motion of gas near the black hole modifies the disk’s luminosity through a phenomenon called Doppler boosting – an effect of Einstein’s relativity theory that brightens the side rotating toward the viewer and dims the side spinning away. The visualization also shows a more subtle phenomenon called relativistic aberration. The black holes appear smaller as they approach the viewer and larger when moving away. These effects disappear when viewing the system from above, but new features emerge. Both black holes produce small images of their partners that circle around them each orbit. Looking closely, it’s clear that these images are actually edge-on views. To produce them, light from the black holes must be redirected by 90 degrees, which means we’re observing the black holes from two different perspectives – face on and edge on – at the same time. Zooming into each black hole reveals multiple, increasingly distorted images of its partner. The visualization, created by astrophysicist Jeremy Schnittman at NASA's Goddard Space Flight Center in Greenbelt, Maryland, involved computing the path taken by light rays from the accretion disks as they made their way through the warped space-time around the black holes. On a modern desktop computer, the calculations needed to make the movie frames would have taken about a decade. So Schnittman teamed up with Goddard data scientist Brian P. Powell to use the Discover supercomputer at the NASA Center for Climate Simulation. Using just 2% of Discover’s 129,000 processors, these computations took about a day. Astronomers expect that, one day, they’ll be able to detect gravitational waves – ripples in space-time – produced when two supermassive black holes in a system much like the one Schnittman depicted spiral together and merge.
  • Black Hole Accretion Disk Visualization
    2019.09.25
    This new visualization of a black hole illustrates how its gravity distorts our view, warping its surroundings as if seen in a carnival mirror. The visualization simulates the appearance of a black hole where infalling matter has collected into a thin, hot structure called an accretion disk. The black hole’s extreme gravity skews light emitted by different regions of the disk, producing the misshapen appearance. Bright knots constantly form and dissipate in the disk as magnetic fields wind and twist through the churning gas. Nearest the black hole, the gas orbits at close to the speed of light, while the outer portions spin a bit more slowly. This difference stretches and shears the bright knots, producing light and dark lanes in the disk. Viewed from the side, the disk looks brighter on the left than it does on the right. Glowing gas on the left side of the disk moves toward us so fast that the effects of Einstein’s relativity give it a boost in brightness; the opposite happens on the right side, where gas moving away us becomes slightly dimmer. This asymmetry disappears when we see the disk exactly face on because, from that perspective, none of the material is moving along our line of sight. Closest to the black hole, the gravitational light-bending becomes so excessive that we can see the underside of the disk as a bright ring of light seemingly outlining the black hole. This so-called “photon ring” is composed of multiple rings, which grow progressively fainter and thinner, from light that has circled the black hole two, three, or even more times before escaping to reach our eyes. Because the black hole modeled in this visualization is spherical and non-rotating, the photon ring looks nearly circular and identical from any viewing angle. Inside the photon ring is the black hole’s shadow, an area roughly twice the size of the event horizon — its point of no return. This visualization is “mass invariant,” which means it can represent a black hole of any mass. The size of the black hole's shadow is proportional to its mass, but so is the size of the accreetion disk, so its properties scale accordingly. Simulations and movies like these really help us visualize what Einstein meant when he said that gravity warps the fabric of space and time.
  • New Simulation Sheds Light on Spiraling Supermassive Black Holes
    2018.10.02
    A new model is bringing scientists a step closer to understanding the kinds of light signals produced when two supermassive black holes, which are millions to billions of times the mass of the Sun, spiral toward a collision. For the first time, a new computer simulation that fully incorporates the physical effects of Einstein’s general theory of relativity shows that gas in such systems will glow predominantly in ultraviolet and X-ray light. The new simulation shows three orbits of a pair of supermassive black holes only 40 orbits from merging. The models reveal the light emitted at this stage of the process may be dominated by UV light with some high-energy X-rays, similar to what’s seen in any galaxy with a well-fed supermassive black hole. Three regions of light-emitting gas glow as the black holes merge, all connected by streams of hot gas: a large ring encircling the entire system, called the circumbinary disk, and two smaller ones around each black hole, called mini disks. All these objects emit predominantly UV light. When gas flows into a mini disk at a high rate, the disk’s UV light interacts with each black hole’s corona, a region of high-energy subatomic particles above and below the disk. This interaction produces X-rays. When the accretion rate is lower, UV light dims relative to the X-rays. Based on the simulation, which ran on the National Center for Supercomputing Applications’ Blue Waters supercomputer at the University of Illinois at Urbana-Champaign, the researchers expect X-rays emitted by a near-merger will be brighter and more variable than X-rays seen from single supermassive black holes. The pace of the changes links to both the orbital speed of gas located at the inner edge of the circumbinary disk as well as that of the merging black holes.

Related Content

We’ve seen black holes flare up, shred stars, trigger star formation in other galaxies, and fire neutrinos toward Earth! These resources cover a broad range of black hole topics as well as NASA’s role in exploring them.
  • Mini-Jet Found Near Milky Way’s Supermassive Black Hole
    2021.12.09
    Our Milky Way’s central black hole has a leak! This supermassive black hole, over 4 million times more massive than our Sun, looks like it still has the remnants of a blowtorch-like jet dating back several thousand years. NASA’s Hubble Space Telescope hasn’t photographed the phantom jet yet, but it has helped find circumstantial evidence that the jet is still pushing feebly into a huge hydrogen cloud. For more information, visit https://nasa.gov/hubble. Music Credits: “Never Sure of Anything” by Andrew Potterton [PRS], via Ninja Tune Production Music [PRS], and Universal Production Music
  • NASA's Fermi Spots 'Fizzled' Burst from Collapsing Star
    2021.07.26
    On Aug. 26, 2020, NASA’s Fermi Gamma-ray Space Telescope detected a pulse of high-energy radiation that turned out to be one for the record books – the shortest gamma-ray burst (GRB) caused by the death of a massive star ever seen. GRBs are the most powerful events in the universe. Astronomers classify them as long or short based on whether the event lasts for more or less than two seconds. They observe long bursts in association with the demise of massive stars, while short bursts have been linked to a different scenario. Named GRB 200826A, the event is definitely a short-duration GRB, but other properties point to its origin from a collapsing star. When a star much more massive than the Sun runs out of fuel, its core suddenly collapses and forms a black hole. As matter swirls toward the black hole, some of it escapes in the form of two powerful jets that rush outward at almost the speed of light in opposite directions. Astronomers only detect a GRB when one of these jets happens to point almost directly toward Earth. Each jet drills through the star, producing a pulse of gamma rays – the highest-energy form of light – that can last up to minutes. Following the burst, the disrupted star then rapidly expands as a supernova. To prove the blast came from a dying star, a team led by Tomás Ahumada, a doctoral student at the University of Maryland, College Park and NASA’s Goddard Space Flight Center in Greenbelt, Maryland, searched for the GRB’s fading afterglow and the emerging light of the supernova explosion that followed. GRB 200826A was a sharp blast of high-energy emission about a second long when it was detected by Fermi’s Gamma-ray Burst Monitor. NASA’s Wind and Mars Odyssey missions also saw it, as did ESA's (the European Space Agency’s) INTEGRAL satellite, which enabled astronomers to narrow the burst's location in the sky. They quickly located the afterglow using the Zwicky Transient Facility (ZTF) at Palomar Observatory. Twenty-eight days after the burst, the team detected the light of a supernova in the burst's host galaxy, proving the blast came from the demise of a massive star. The astronomers describe the GRB as a fizzle, where weak jets lasted just long enough to breach the star's surface before shutting down. If the jets had been any weaker, the burst might not have occurred at all.
    El 26 de agosto de 2020, el telescopio espacial de rayos gamma Fermi de la NASA detectó un pulso de radiación de alta energía que resultó ser uno para los libros de récords – el brote de rayos gamma más corto causado por la muerte de una estrella masiva jamás visto. Los brotes de rayos gamma (GRB por sus siglas en inglés) son los eventos más potentes del universo. Los astrónomos los clasifican como largos o cortos en función de si el evento dura más o menos de dos segundos. Los brotes de rayos gamma largos se observan en asociación con la muerte de estrellas masivas, mientras que los estallidos cortos se han relacionado con un escenario diferente. Nombrado GRB 200826A, el evento es definitivamente un GRB de corta duración, pero otras de sus propiedades apuntan a que su origen es una estrella que colapsó. Cuando una estrella mucho más masiva que el Sol se queda sin combustible, su núcleo colapsa repentinamente y forma un agujero negro. A medida que la materia cae hacia el agujero negro, parte de ella escapa en forma de dos potentes chorros que se precipitan hacia el exterior casi a la velocidad de la luz en direcciones opuestas. Los astrónomos sólo detectan un GRB cuando uno de estos chorros apunta casi directamente hacia la Tierra. Cada chorro perfora la estrella, produciendo un pulso de rayos gamma – la forma de luz de mayor energía y – que puede durar hasta minutos. Después del estallido, la estrella se expande rápidamente como una supernova. Para demostrar que la explosión provino de una estrella moribunda, un equipo dirigido por Tomás Ahumada, un estudiante de doctorado en la Universidad de Maryland, College Park y el Centro de Vuelo Espacial Goddard de la NASA en Greenbelt, Maryland, buscó el resplandor del GRB y la luz emergente proveniente de la supernova que le siguió. El GRB 200826A fue una breve explosión de emisión de alta energía que duró aproximadamente un segundo de duración cuando fue detectada por el monitor de ráfagas de rayos gamma de Fermi. Las misiones Wind y Mars Odyssey de la NASA también lo detectaron, al igual que el satélite INTEGRAL de la ESA (la Agencia Espacial Europea), lo que permitió a los astrónomos reducir la ubicación de la explosión en el cielo. Rápidamente localizaron el resplandor posterior a la explosión utilizando la Zwicky Transient Facility (ZTF) en el Observatorio Palomar. Veintiocho días después de la explosión, el equipo detectó la luz de una supernova en la galaxia anfitriona de la explosión, lo que demuestra que la explosión provino de la muerte de una estrella masiva. Los astrónomos describen este GRB como una fuga de rayos gamma, donde los chorros débiles duraron justo lo suficiente como para romper la superficie de la estrella antes de apagarse. Si el GRB hubiese sido ligeramente mas débil, el estallido podrían no haber ocurrido en absoluto.
  • M87: Telescopes Unite in Unprecedented Observations of Famous Black Hole
    2021.04.21
    Beginning with the Event Horizon Telescope's now iconic image of the black hole at the center of M87, a new video takes viewers on a journey through the data from each telescope. The video shows data across many factors of 10 in scale, both of wavelengths of light and physical size. In April 2019, scientists released the first image of a black hole in the galaxy M87 using the Event Horizon Telescope (EHT). This supermassive black hole weighs 6.5 billion times the mass of the Sun and is located at the center of M87, about 55 million light-years from Earth. The supermassive black hole is powering jets of particles that travel at almost the speed of light, as described in the press release. These jets produce light spanning the entire electromagnetic spectrum, from radio waves to visible light to gamma rays. To gain crucial insight into the black hole's properties and help interpret the EHT image, scientists coordinated observations with 19 of the world's most powerful telescopes on the ground and in space, collecting light from across the spectrum. This is the largest simultaneous observing campaign ever undertaken on a supermassive black hole with jets. The Astrophysical Journal Letter describing these results is available here. The NASA telescopes involved in this observing campaign included the Chandra X-ray Observatory, Hubble Space Telescope, Neil Gehrels Swift Observatory, the Nuclear Spectroscopic Telescope Array (NuSTAR), and the Fermi Gamma-ray Space Telescope. The sequence begins with the Event Horizon Telescope(EHT) image of the black hole. It then moves through images from other radio telescope arrays from around the globe, moving outward in the field of view during each step. (The scale for the width of squares is given in light-years in the bottom right). Next, the view changes to telescopes that detect visible light (Hubble and Swift), ultraviolet light (Swift), and X-rays (Chandra and NuSTAR). The screen splits to show how these images, which cover the same amount of the sky, compared to one another. The sequence finishes by showing what gamma-ray telescopes on the ground, and Fermi in space, detect from this black hole and its jet. Throughout the sequence, the smallest detail that the array or telescope can see increases in size by a large amount. For example the smallest details that the EHT, Chandra, and Fermi can see are less than 0.01 light-year, about 100 light-years, and greater than 100,000 light-years, respectively. Only the EHT can detect the black hole's shadow, and at the other extreme, Fermi is not able to determine whether the gamma-ray emission it detects comes from regions close to the black hole or from the jet. The data were collected by a team of 760 scientists and engineers from nearly 200 institutions, 32 countries or regions, using observatories funded by agencies and institutions around the globe. The observations were concentrated from the end of March to the middle of April 2017. Additional information and related imagery can be found on the Chandra X-Ray Observatory site
  • Swift Links Neutrino to Star-destroying Black Hole
    2021.02.22
    For only the second time, astronomers have linked an elusive particle called a high-energy neutrino to an object outside our galaxy. Using ground- and space-based facilities, including NASA’s Neil Gehrels Swift Observatory, they traced the neutrino to a black hole tearing apart a star, a rare cataclysmic occurrence called a tidal disruption event. Neutrinos are fundamental particles that far outnumber all the atoms in the universe but rarely interact with other matter. Astrophysicists are particularly interested in high-energy neutrinos, which have energies up to 1,000 times greater than those produced by the most powerful particle colliders on Earth. They think the most extreme events in the universe, like violent galactic outbursts, accelerate particles to nearly the speed of light. Those particles then collide with light or other particles to generate high-energy neutrinos. The first confirmed high-energy neutrino source, announced in 2018, was a type of active galaxy called a blazar. Tidal disruption events occur when an unlucky star strays too close to a black hole. Gravitational forces create intense tides that break the star apart into a stream of gas. The trailing part of the stream escapes the system, while the leading part swings back around, surrounding the black hole with a disk of debris. In some cases, the black hole launches fast-moving particle jets. Scientists hypothesized that tidal disruptions would produce high-energy neutrinos within such particle jets. They also expected the events would produce neutrinos early in their evolution, at peak brightness, whatever the particles’ production process. Tidal disruption event AT2019dsg was discovered on April 9, 2019, by the Zwicky Transient Facility (ZTF), a robotic camera at Caltech’s Palomar Observatory in Southern California. The event occurred over 690 million light-years away in a galaxy called 2MASX J20570298+1412165, located in the constellation Delphinus. As part of a routine follow-up survey of tidal disruptions, scientists requested visible, ultraviolet, and X-ray observations with Swift. They also took X-ray measurements using the European Space Agency’s XMM-Newton satellite and radio measurements with facilities including the National Radio Astronomy Observatory’s Karl G. Jansky Very Large Array in Socorro, New Mexico, and the South African Radio Astronomy Observatory's MeerKAT telescope. Peak brightness came and went in May. No clear jet appeared. According to theoretical predictions, AT2019dsg was looking like a poor neutrino candidate. Then, on Oct. 1, 2019, the National Science Foundation’s IceCube Neutrino Observatory at the Amundsen-Scott South Pole Station in Antarctica detected a high-energy neutrino called IC191001A and backtracked along its trajectory to a location in the sky. About seven hours later, ZTF noted that this same patch of sky included AT2019dsg. Astronomers think there is only one chance in 500 that the tidal disruption is not the neutrino’s source. Because the detection came about five months after the event reached peak brightness, it raises questions about when and how these occurrences produce neutrinos.
  • Hubble Uncovers Concentration of Small Black Holes
    2021.02.11
    Astronomers on the hunt for an intermediate-mass black hole at the heart of the globular cluster NGC 6397, found something they weren’t expecting: a concentration of smaller black holes lurking there instead of one massive black hole. For more information, visit https://nasa.gov/hubble. Music Credits: "Glass Ships" by Chris Constantinou [PRS] and Paul Frazer [PRS] via Killer Tracks [BMI] and Universal Production Music. Visual Credits: Artist’s Impression of the Black Hole Concentration in NGC 6397 Video credit: ESA/Hubble, N. Bartmann Callout of the Black Hole Concentration in NGC 6397 Video credit: ESA/Hubble, N. Bartmann Artist Rendition of Gaia Spacecraft Image credit: ESA, C. Carreau
  • Swift, TESS Catch Eruptions from an Active Galaxy
    2021.01.12
    Using data from facilities including NASA’s Neil Gehrels Swift Observatory and Transiting Exoplanet Survey Satellite (TESS), scientists have studied 20 instances and counting of regular outbursts of an event called ASASSN-14ko. Astronomers classify galaxies with unusually bright and variable centers as active galaxies. These objects can produce much more energy than the combined contribution of all their stars, including higher-than-expected levels of visible, ultraviolet, and X-ray light. Astrophysicists think the extra emission comes from near the galaxy’s central supermassive black hole, where a swirling disk of gas and dust accumulates and heats up because of gravitational and frictional forces. The black hole slowly consumes the material, which creates random fluctuation in the disk’s emitted light. But astronomers are interested in finding active galaxies with flares that happen at regular intervals, which might help them identify and study new phenomena and events. ASASSN-14ko was first detected on Nov. 14, 2014, by the All-Sky Automated Survey for Supernovae (ASAS-SN), a global network of 20 robotic telescopes. It occurred in ESO 253-3, an active galaxy over 570 million light-years away in the southern constellation Pictor. At the time, astronomers thought the outburst was most likely a supernova, a one-time event that destroys a star. Six years later, scientists examined the ESO 253-3 ASAS-SN light curve, or the graph of its brightness over time, and noticed a series of evenly spaced flares – a total of 17, all separated by 114 days. Each flare reaches its peak brightness in about five days, then steadily dims. They predicted that the galaxy would flare again on May 17, 2020, so they coordinated joint observations with ground- and space-based facilities, including multiwavelength measurements with Swift. ASASSN-14ko erupted right on schedule. Subsequent flares were predicted and observed on Sept. 7 and Dec. 20. Using measurements of these and previous flares from ASAS-SN, TESS, Swift and other observatories, including NASA’s NuSTAR and the European Space Agency’s XMM-Newton, scientists propose the repeating flares are most likely a partial tidal disruption event. A tidal disruption event occurs when an unlucky star strays too close to a black hole. Gravitational forces create intense tides that break the star apart into a stream of gas. The trailing part of the stream escapes the system, while the leading part swings back around the black hole. Astronomers see bright flares from these events when the shed gas strikes the black hole’s accretion disk. In this case, the astronomers suggest that one of the galaxy’s supermassive black holes, one with about 78 million times the Sun’s mass, partially disrupts an orbiting giant star. The star's orbit isn’t circular, and each time it passes closest to the black hole, it bulges outward, shedding mass but not completely breaking apart. Every encounter strips away an amount of gas equal to about three times the mass of Jupiter.
  • Hubble Science: Black Holes, From Myth to Reality
    2020.11.27
    For the past 30 years the Hubble Space Telescope has continued its important mission of uncovering the mysteries of the universe. One of those mysteries that Hubble has helped us understand are black holes. For more information, visit https://nasa.gov/hubble. Videos & Images: NASA Goddard Space Flight Center European Space Agency Music: “Transitions” by Ben Niblett [PRS] and Jon Cotton [PRS] via Atmosphere Music Ltd [PRS] and Universal Production Music.
  • Young Active Galaxy with ‘TIE Fighter’ Shape
    2020.08.25
    Not so long ago, astronomers mapped a galaxy far, far away using radio waves and found it looked strikingly similar to Darth Vader’s TIE fighter spacecraft in “Star Wars: Episode IV – A New Hope.” In the process, they discovered the object, called TXS 0128+554, experienced two powerful bouts of activity in the last century.

    Around five years ago, NASA’s Fermi Gamma-ray Space Telescope reported that TXS 0128+554 (TXS 0128 for short) is a faint source of gamma rays, the highest-energy form of light. Scientists have since taken a closer look using the Very Long Baseline Array (VLBA) and NASA’s Chandra X-ray Observatory.

    TXS 0128 lies 500 million light-years away in the constellation Cassiopeia, anchored by a supermassive black hole around 1 billion times the Sun’s mass. It’s classified as an active galaxy, which means all its stars together can’t account for the amount of light it emits.

    Researchers added the galaxy to a long-running survey conducted by the VLBA, a network of radio antennas operated by the National Radio Astronomy Observatory stretching from Hawaii to the U.S. Virgin Islands.

    The array’s measurements provide a detailed map of TXS 0128 at different radio frequencies. The radio structure they revealed spans 35 light-years across and tilts about 50 degrees out of our line of sight. This angle means the jets aren’t pointed directly at us and may explain why the galaxy is so dim in gamma rays.

    The radio emission also sheds light on the location of the galaxy’s gamma-ray signal. Many theorists predicted that young, radio-bright active galaxies produce gamma rays when their jets of high-energy particles collide with intergalactic gas. But in TXS 0128’s case, at least, the particles don’t produce enough combined energy to generate the detected gamma rays. Instead, Lister’s team thinks the galaxy’s jets produce gamma rays closer to the core, like the majority of active galaxies Fermi sees.

  • Hubble Finds Evidence of Mid-Sized Black Hole
    2020.03.31
    Astronomers have identified a black hole of an elusive class known as “intermediate-mass,” which betrayed its existence by tearing apart a wayward star that passed too close. This exciting discovery opens the door to the possibility of many more lurking undetected in the dark, waiting to be given away by a star passing too close. For more information about the Hubble Space Telescope and its images, visit: https://nasa.gov/hubble Music Credits: “Struck by the Beauty” by Emmanuel David Lipszyc [SACEM], Sébastien Lipszyc [SACEM], and Thomas Bloch [SACEM]. Koka Media [SACEM], and Universal Production Music.
  • OSIRIS-REx Observes a Black Hole
    2020.03.02
    University students and researchers working on a NASA mission orbiting a near-Earth asteroid have made an unexpected detection of a phenomenon 30 thousand light years away. Last fall, the student-built Regolith X-Ray Imaging Spectrometer (REXIS) onboard NASA’s OSIRIS-REx spacecraft detected a newly flaring black hole in the constellation Columba while making observations off the limb of asteroid Bennu. The glowing object turned out to be a newly flaring black hole X-ray binary – discovered just a week earlier by Japan’s MAXI telescope – designated MAXI J0637-430.
  • 5 Things: Black Holes
    2019.11.27
    Join NASA Goddard scientists on 11/29/19 from 1-3 p.m. EDT for a #BlackHoleFriday Q&A on Instagram, Twitter, Facebook and YouTube.

    Music: Dramedy Percs and Pizz from Universal Music Production

  • TESS Catches Its First Star-destroying Black Hole
    2019.09.26
    NASA’s planet-hunting Transiting Exoplanet Survey Satellite (TESS) watched a black hole tear apart a star from start to finish, a cataclysmic phenomenon called a tidal disruption event. The blast, named ASASSN-19bt, was found on Jan. 29 by the All-Sky Automated Survey for Supernovae (ASAS-SN), a worldwide network of 20 robotic telescopes. Shortly after the discovery, ASAS-SN requested follow-up observations by NASA’s Swift satellite, ESA’s (European Space Agency’s) XMM-Newton and ground-based 1-meter telescopes in the global Las Cumbres Observatory network. The disruption occurred in TESS’s continuous viewing zone, which is always in sight of one of the satellite’s four cameras. This allowed astronomers to view the explosion from beginning to end.
  • Zoom In on Galaxy M87
    2019.09.24
    This movie zooms into galaxy M87 using real visible light, X-ray and radio pictures of the galaxy, its jet of high-speed particles, and the shadow of its central black hole.
  • NICER Charts the Area Around a New Black Hole
    2019.01.30
    Scientists have mapped the environment surrounding a black hole that is 10 times the mass of the Sun using NASA’s Neutron star Interior Composition Explorer (NICER) payload aboard the International Space Station. NICER detected X-ray light from a recently discovered black hole, called MAXI J1820+070 (J1820 for short), as it consumed material from a companion star. Waves of X-rays formed "light echoes" that reflected off the swirling gas near the black hole and revealed changes in the environment’s size and shape. A black hole can siphon gas from a nearby star and into a ring of material called an accretion disk that glows in X-rays. Above this disk is the corona, a region of subatomic particles that glows in higher-energy X-rays. Astrophysicists want to better understand how the inner edge of the accretion disk and the corona change in size and shape as a black hole accretes material from its companion star. If they can understand how and why these changes occur in stellar-mass black holes over a period of weeks, they could shed light on how supermassive black holes evolve over millions of years and how they affect the galaxies in which they reside. One method used to chart those changes is called X-ray reverberation mapping, which uses X-ray reflections in much the same way sonar uses sound waves to map undersea terrain. From 10,000 light-years away, the scientists estimated that the corona contracted vertically from roughly 100 to 10 miles — that’s like seeing something the size of a blueberry shrink to something the size of a poppy seed at the distance of Pluto.
  • X-ray Echoes Map a 'Killer' Black Hole
    2016.06.22
    Some 3.9 billion years ago in the heart of a distant galaxy, the tidal pull of a monster black hole shredded a star that wanderd too close. X-rays produced in this event first reached Earth on March 28, 2011, when they were detected by NASA's Swift satellite. Within days, scientists concluded that the outburst, now known as Swift J1644+57, represented both the tidal disruption of a star and the sudden flare-up of a previously inactive black hole. Now astronomers using archival observations from Swift, the European Space Agency's XMM-Newton observatory and the Japan-led Suzaku satellite have identified the reflections of X-ray flares erupting during the event. Led by Erin Kara, a postdoctoral researcher at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and the University of Maryland, College Park, the team has used these light echoes, or reverberations, to map the flow of gas near a newly awakened black hole for the first time. Swift J1644+57 is one of only three tidal disruptions that have produced high-energy X-rays, and to date it remains the only event caught at the peak of this emission. While astronomers don't yet understand what causes flares near the black hole, when one occurs they can detect its echo a couple of minutes later as its light washes over structures in the developing accretion disk. The technique, called X-ray reverberation mapping, has been used before to explore stable disks around black holes, but this is time it has been applied to a newly formed disk produced by a tidal disruption. Swift J1644+57's accretion disk was thicker, more turbulent and more chaotic than stable disks, which have had time to settle down into an orderly routine. One surprise is that high-energy X-rays arise from the innermost regions of the disk instead of a narrow jet of accelerated particles, as originally thought. The researchers estimate the black hole has a mass about a million times that of the sun. They expect future improvements in understanding and modeling accretion flows will allow them to measure the black hole's spin using this data.
  • A Black Hole Visits Baltimore
    2015.09.25
    This scientific visualization demonstrates the visual distortion known as gravitational lensing. A black hole, with roughly the mass of the planet Saturn, is imagined to pass over the Inner Harbor in Baltimore, MD. The view of the buildings on the far side of the harbor are distorted using the calculated effects of Einstein's general relativity.
    A black hole warps the space around it. Light that passes near a black hole will follow curved paths and can create multiple images and other visual artifacts. Note that the sky can sometimes be seen by looking below the black hole. These distortions are similar to what can be produced using glass lenses, and are produced by similar optics equations. The effects are called gravitational lensing - lensing that redirects light using mass instead of glass.
    The calculations for the visualization use a planar approximation that assumes the buildings are all at the same distance, but are otherwise accurate. Note also that foreground objects, like the boat mast, were not isolated and removed from the image before distortion. In a fully accurate visualization, foreground objects would not be distorted.
  • Turning Black Holes into Dark Matter Labs
    2015.06.23
    A new computer simulation tracking dark matter particles in the extreme gravity of a black hole shows that strong, potentially observable gamma-ray light can be produced. Detecting this emission would provide astronomers with a new tool for understanding both black holes and the nature of dark matter, an elusive substance accounting for most of the mass of the universe that neither reflects, absorbs nor emits light. Jeremy Schnittman, an astrophysicist at NASA's Goddard Space Flight Center, developed a computer simulation to follow the orbits of hundreds of millions of dark matter particles, as well as the gamma rays produced when they collide, in the vicinity of a black hole. He found that some gamma rays escaped with energies far exceeding what had been previously regarded as theoretical limits. In the simulation, dark matter takes the form of Weakly Interacting Massive Particles, or WIMPS, now widely regarded as the leading candidate class. In this model, WIMPs that crash into other WIMPs mutually annihilate and convert into gamma rays, the most energetic form of light. But these collisions are extremely rare under normal circumstances. Over the past few years, theorists have turned to black holes as dark matter concentrators, where WIMPs can be forced together in a way that increases both the rate and energies of collisions. The concept is a variant of the Penrose process, first identified in 1969 by British astrophysicist Sir Roger Penrose as a mechanism for extracting energy from a spinning black hole. The faster it spins, the greater the potential energy gain. In this process, all of the action takes place outside the black hole's event horizon, the boundary beyond which nothing can escape, in a flattened region called the ergosphere. Within the ergosphere, the black hole's rotation drags space-time along with it and everything is forced to move in the same direction at nearly speed of light. This creates a natural laboratory more extreme than any possible on Earth. Previous work indicated that the maximum gamma-ray energy from the collisional version of the Penrose process was only about 1.3 times the rest mass of the annihilating particles. In addition, only a small portion of high-energy gamma rays managed to escape the ergosphere. These results suggested that a conclusive annihilation signal might never be seen from a supermassive black hole. However, earlier work made simplifying assumptions about the locations of the highest-energy collisions. Schnittman's model instead tracks the positions and properties of hundreds of millions of randomly distributed particles as they collide and annihilate near a black hole. The new model reveals processes that produce gamma rays with much higher energies, as well as a better likelihood of escape and detection, than ever thought possible. He identified previously unrecognized trajectories where collisions produce gamma rays with a peak energy 14 times the rest mass of the annihilating particles. The simulation tells astronomers that there is an astrophysically interesting signal they may be able to detect as gamma-ray telescopes improve.