2002 SPACE SCIENCE VIDEOTAPES |
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Tape Title | Record ID | Date Produced | TRT: |
Synopsis |
| STRANGE UNIVERSE: DELVING DEEP INTO BLACK HOLES | G02-046 | 7/3/02 | 00:45:17 |
Black holes are perhaps the strangest objects in the cosmos. A black hole’s gravity is so intense that nothing, not even light, can escape its pull once inside the black hole’s boundary, called the event horizon. They are of interest to astronomers because their extreme gravity causes some of the bizarre effects predicted by Einstein’s Theory of Relativity to manifest themselves. For example, time slows down near a black hole. If you and some friends were in a spaceship orbiting a black hole, and your friends (unwisely) decide to don spacesuits and venture into the black hole while you remain behind, you would notice that their movements, or if you could see them, their wristwatches, would become slower and slower as they approached the black hole, until, right at the event horizon, they appeared frozen in time.
Black holes come in a range of sizes, determined by their mass. The black holes formed from the core of an exploding star, called stellar-mass black holes, typically have the mass of 4 to 15 Suns. Intermediate-mass black holes are equivalent to thousands of Suns, and supermassive black holes weigh in at millions to billions of Suns.
Since light can’t escape from black holes, they can’t be seen directly. However, they reveal their presence by their strong pull on nearby matter. If a black hole happens to be orbiting a nearby star, it pulls gas from the star, which swirls around the black hole before plunging in, like water down a drain. As the gas whirls around the black hole, friction and compression cause the gas to become intensely hot, and it shines brightly in high-energy radiation like X-rays, betraying the black hole’s presence. In fact, supermassive black holes are thought to be the engines powering the brightest beacons in the universe, the quasars, by feeding on gas in the centers of galaxies and shining with the light of trillions of Suns.
Stellar-mass black holes are created when a star at least 10 to 15 times as massive as the Sun loses its life-long battle with gravity. The tremendous amount of matter in a star generates strong gravity, which causes the star to contract. The compression crushes matter at the center of the star so fiercely that its atoms fuse together, releasing terrific energy and causing the star to shine. Radiation and heat from this nuclear fusion oppose the gravity, causing the star to expand. As long as the star has fuel, fusion opposes gravitational contraction and the star’s size is balanced. However, when a star exhausts its fuel at the end of its life, gravity’s embrace is unimpeded. The core collapses under its own gravity, and the star’s outer layers are blown off in a catastrophic supernova explosion. Depending on the core’s mass, it may become one of a variety of exotic, ultra-dense objects. If the core is sufficiently massive, nothing can halt its collapse, and it becomes a black hole. It is not yet known how intermediate-mass and supermassive black holes form, but one theory is that they result from the merger of many stellar-mass black holes. Trying to understanding gravity is key to unraveling the essence of time, matter and energy. Nowhere is gravity more extreme than at a black hole. Studying black holes is part of NASA's Structure and Evolution of the Universe Program.
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TAPE CONTENTS: |
| THE IMAGES :
ITEM (1) Black Hole With Event Horizon - Animation dives through the bulge and into the center of a spiral galaxy. At the center of the galaxy is a supermassive black hole.
CREDIT: NASA/ST ScI
ITEM (2) Active Black Hole in NGC 4261 - This animation shows Galaxy NGC 4261 as an active black hole disk and jet model. Astronomers have discovered a remarkable correlation between a black hole's mass and the average speed of the stars in the galaxy's central bulge. The faster the stars are moving, the more massive the black hole. This suggests the galaxy and the black hole grew simultaneously.
CREDIT: NASA/ST ScI
ITEM (3) Centaurus A: Feeding a Black Hole - From the NICMOS image we have seen that behind the obscuring dust, inside the Centaurus A Galaxy, there are a hot gas disk and a twisted jet and disk around a feeding black hole.
CREDIT: NASA/Thomas Goertel/ST Sci
ITEM (4) Two New Types Of Objects Discovered (G00-003-02) - Observations showed that nearly one third of the sources are galaxies whose cores are very bright in X-rays yet emit virtually no optical light from the core. The observation suggests that these "veiled galactic nuclei" galaxies may number in the tens of millions over the whole sky. They almost certainly harbor a massive black hole at their core that produced X-rays as the gas is pulled toward it at nearly the speed of light.
CREDIT: NASA/MSFC/CXC
ITEM (5) Chandra Black Hole Animation (G02-046-04) - This animation illustrates the activity surrounding a black hole. While the matter that has passed the black hole's "event horizon" can't be seen, material swirling outside this threshold is accelerated to millions of degrees and radiates in X-rays. At the end of the animation, the black hole is shown shrouded in a cloud of gas and dust, obscuring it from most angles at wavelengths other than the X-rays picked up by the Chandra X-ray Observatory.
CREDIT: NASA/MSFC/CXC/A.Hobart)
ITEM (6) Animation of Event Horizon in Cygnus XR-1 (G02-046-05) - Animation depicts the event horizon of the black hole in Cygnus XR-1. As the camera zooms in, a clump of material breaks off from the accretion disk and spirals in toward the event horizon at the center. As the clump falls in, its light gets shifted from blue-white to red and it gives off a series of pulses, detected by the Hubble Space Telescope's High-Speed Photometer.
CREDIT: NASA/ST ScI
ITEM (7) Colliding Black Holes (G02-046-06) - In this time lapse movie of images taken by the Chandra X-ray Observatory, it zooms into the inner region of the galaxy M82, and shows the dramatic increase in the intensity of the bright source that is associated with a mid-mass black hole.
CREDIT: NASA/MSFC/CXC/SAO
ITEM (8) Chandra Image - Extended X-Ray Jets (G02-046-07) - NASA's Chandra X-ray Observatory has made an extraordinary image of Centaurus A, a nearby galaxy noted for its explosive activity. The image shows an X-ray jet erupting from the center of the galaxy over a distance of 25,000 light years. Also detected are a group of X-ray sources clustered around the nucleus, which is believed to hold a supermassive black hole.
CREDIT: NASA/MSFC/CXC/SAO
ITEM (9) HCG 62: Chandra Captures Remarkable Image of Galaxy Group (G02-046-08) - Perhaps the most striking features of this Chandra X-ray image of HCG 62 are the two cavities that appear nearly symmetrically opposite one another (upper left and lower right) in the hot, X-ray emitting gas. These cavities might be explained by the presence of X-ray absorbing material, but are more likely due to jets of particles recently emitted from the core of NGC 4761, the central elliptical galaxy of HCG 62, although no such jets are visible today. PRE>
CREDIT: NASA/MSFC/CfA/J. Vrtilek et al.
ITEM (10) Cygnus A: Catching a Galactic Football (G02-046-09) - This Chandra image shows a giant football-shaped cavity (yellow/light orange inner region) within X-ray emitting hot gas surrounding the galaxy Cygnus A. The cavity in the hot gas has been created by two powerful jets emitted from the central black hole region in the nucleus of Cygnus A. Hot gas is steadily being piled up around the cavity as it continuously expands, creating a bright rim of X-ray emission (bright orange outer area). Cygnus A is not alone in its galactic neighborhood, but is a member of a large cluster containing many galaxies. Extremely hot (tens of millions of degrees Celsius) gas is spread between the galaxies. Although it has a very low density, this gas provides enough resistance to slow down the outward advancement of the particle jets from Cygnus A. The jets themselves terminate in radio and X-ray emitting "hot spots" some 300,000 light years from the center of the galaxy. Scientists believe that fast atomic particles and magnetic fields from the jets spill out into the region, providing pressure that continuously inflates the cavity.
CREDIT: NASA/MSFC/UMD/A.Wilson et al.
ITEM (11) The Antennae: Chandra Finds Abundance of Ultraluminous X-Ray Sources (G02-046-10) - This Chandra X-ray image shows the central regions of two colliding galaxies known collectively as "The Antennae." The latest Chandra data reveal a large population of extremely bright X-ray sources in this area of intense star formation. These "ultraluminous" X-ray sources, which emit 10 to several hundred times more X-ray power than similar sources in our own Galaxy, are believed to be either massive black holes, or black holes that are beaming their energy toward Earth. In this X-ray image, red represents the low energy band, green intermediate and blue the highest observed energies. The white and yellow sources are those that emit significant amounts of both low- and high-energy X-rays. The Antennae Galaxies, about 60 million light years from Earth in the constellation Corvus, got their nickname from the wispy antennae-like streams of gas seen by optical telescopes. These wisps are believed to have been produced by the collision between the galaxies that began about 100 million years ago and is still occurring.
CREDIT: NASA/MSFC/SAO/CXC/G.Fabbiano et al.
ITEM (12) Centaurus A: A Nearby Elliptical Galaxy With an Active Galactic Nucleus (G02-046-11) - A nearby massive elliptical galaxy with an active galactic nucleus in the constellation Centaurus. Over 200 point-like X-ray sources have been identified and studied in Cen A. Because of their distribution around the center of the galaxy, it is believed that most of these sources are X-ray binaries in which a neutron star or stellar-sized black hole is accreting matter from a nearby companion star. A few may be supernova remnants or unrelated, more distant background galaxies. Comparison of Cen A's X-ray binary population with populations in other galaxies is important for understanding the evolutionary history of galaxies.
CREDIT: NASA/MSFC/SAO/R.Kraft et al.
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THE SCIENCE New Energy Source Taps Power From Black Hole Spin (G01-070) - Black holes in space are notorious as the ultimate consumers, swallowing everything that crosses their paths, but scientists for the first time have seen energy escape a black hole. Magnetic fields surrounding a black hole take energy contained in the black hole's spin and transfer it to surrounding gas, generating power like a massive celestial flywheel. The black hole power transfer makes the gas, already intensely hot due to the crushing force of the black hole's gravity, even hotter. An international team of astronomers observed the novel "power tapping" around a supermassive black hole in the core of a galaxy named MCG 6-30-15 using the European Space Agency's XMM-Newton X-ray satellite. The observation also may explain the origin of particle jets in quasars, remote celestial beacons that shine with the light of trillions of Suns and are thought to be energized by supermassive black holes.
ITEM (13) Power-Tapping Black Hole Animation (G01-070-01) (two versions) - Gravity in the region of the black hole appears to be so intense that the very fabric of space twists around the black hole, dragging magnetic field lines along with it. The magnetic fields tighten about the black hole, slowing its spin. This 'friction' heats the region to even higher temperatures. According to theory, rotational energy can escape from the black hole as it is braked by magnetic fields. The first law of thermodynamics (conservation of energy) states that energy lost from the black hole must be absorbed by the region around it. The energy lost to the black hole in MCG 6-30-15 is transferred to the inner edge of the accretion disk, a flow of gas swirling around and eventually falling into the black hole. The energy transfer causes the gas to shine even more brightly. In the animation, the rate at which the black hole slows down is greatly exaggerated to illustrate the concept.
CREDIT: NASA/GSFC
Light on The Edge of Oblivion Reveals Black Holes Spin (G01-036) - As if black holes couldn't be more menacing, astronomers now have observational evidence that at least some of them spin about like whirlpools, wrapping up the fabric of space-time with them.
ITEM (14) Spinning Black Hole Animation (G01-036-01) - Almost every kind of object in space spins, such as planets, stars, galaxies. With black holes, it's much harder to directly see they are spinning, because they don't have a solid surface that you can watch spin around. We can, however, see the light emitted from matter plunging into the black hole. The matter cannibalized from the black holes binary companion star, whips frantically around the black hole before it is lost forever.
CREDIT: NASA/GSFC
ITEM (15) Bending Space And Time - The Spinning Black Hole (G01-036-02) - A spinning black hole modifies the fabric of space-time near it. The spinning allows matter to orbit at a closer distance than if it were not spinning, and the closer matter can get the faster it can orbit. These animations examine a spinning black hole. The space-time fabric, represented by the grid overlay, is bent.
CREDIT: NASA/GSFC
ITEM (16) A Non Spinning Black Hole (G01-036-03) - These animations show a non-spinning black hole. Note that space-time fabric, represented by the grid overlay is not bent.
CREDIT: NASA/GSFC
ITEM (17) No Spin/Spin Comparison (G01-036-04) - The spinning allows matter to orbit at a closer distance than if it were not spinning, and the closer matter can get the faster it can orbit. This side-by-side comparison illustrates the differences in the size of the innermost stable orbit between spinning and non-spinning black holes.
CREDIT: NASA/GSFC
RXTE "Old Faithful" Black Hole (G98-001) - Compelling new animation shows a black hole in our galaxy that is hurling away a mass equivalent to a 100 trillion ton asteroid every half hour. The black hole, which is orbiting a close "companion" star, pulls gas from the surface of the star. This gas forms a disk around the black hole. (accretion disk) On approximately half-hour intervals, a disruption occurs and the material is ejected in oppositely directed jets at nearly the speed of light (about 650 million mph), and the cycle repeats itself.
ITEM (18) "Old Faithful" Black Hole Animation (G98-001-01) (2 Versions) - Compelling new animation shows a black hole in our galaxy that is hurling away a mass equivalent to a 100 trillion ton asteroid every half hour. The black hole, which is orbiting a close "companion" star, pulls gas from the surface of the star. This gas forms a disk around the black hole. On approximately half hour intervals, a disruption is transmitted through the disk, the material is ejected in oppositely directed jets at nearly the speed of light (about 650 million miles per hour), and the cycle repeats itself. The energy involved in each ejection is about six trillion times greater than the annual energy consumption of the entire United States.
CREDIT: NASA/GSFC
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| CONFIRMING EINSTEIN'S THEORY Black Hole Twists Space (G97-037/G97-106) - Einstein’s predicted a phenomenon called "frame dragging." This bizarre effect, first predicted by Einstein in 1918, has finally been observed by NASA's Rossi X-ray Timing Explorer (RXTE) spacecraft. This animation illustrates how this phenomenon, called "frame dragging," distorts the space-time near a black hole and the orbits of objects around it. Everyone has seen movies where a spaceship falls into a black hole. Did you know that it is impossible to fall straight in? A black hole's gravity is so intense that it actually drags space with it as it rotates, much like a ball spinning in molasses. When the ball rotates, it will drag the molasses around with it, as well as any objects that happen to be stuck in the molasses. In the same way, an object falling directly into a black hole will be dragged around with the space near the black hole before finally falling in.
ITEM (19) "Frame Dragging" (G97-037-01) - This Animation traces the paths of matter that is falling in toward a spinning black hole. Because the gravitational field near the black hole is so intense, the black hole is literally dragging space and time around itself as it rotates; an effect called frame dragging. The animation illustrates the distorted paths material would take if it approached the black hole from different angles. The yellow line represents a path made by an object that was initially directed to a head-on collision with the black hole. As it got close to the black hole, the space-time that was being dragged around the black hole dragged the object along with it, forcing it to spiral inward rather than follow a straight line. Similarly, the green line is the path of an object that was initially heading in a direction opposite that of the black hole’s rotation. As it approached the hole, the distorted space-time forced the object to change directions and follow the rotation of the black hole.
CREDIT: NASA/GSFC
ITEM (20) Distorting Space & Time (G97-037-02) - Animation represents the space-time distortion caused by a massive, rotating object. It is a top view of a two-dimensional space-time grid that has been twisted by a massive object in the center. The twisting is in the direction of the object’s rotation. The object’s gravitational field is so intense that space and time are actually being dragged around with the object as it rotates. .
CREDIT: NASA/GSFC
ITEM (21) Neutron Stars (G97-037-05) - Images of neutron stars taken by the Hubble Space Telescope. The detection of frame dragging around neutron stars -- another type of very dense, fast spinning objects --led researchers to seek the same effect near black holes..
CREDIT: NASA/GSFC
For Latest News on Space-Time Curvature, Tune to The AM (G00-072) - Scientists have uncovered sets of oscillating X-ray signals from three neutron stars that may tell the story of the bending of the fabric of space-time around these objects, much like an AM radio signal carries the details of a science talk show buried within its set of radio waves.
ITEM (22) Extreme Gravity -- Bending Time And Space (G00-072-01) - NASA's Rossi X-ray Timing Explorer (RXTE) has previously detected very rapid oscillations in the brightness of X-ray-emitting neutron stars, evidence of a curvature in space-time. Scientists are now seeing sidebands, another set of oscillations that provide even more detail about this world of extreme gravity. This is important new information needed to describe the environs of these fascinating objects.
CREDIT: NASA/GSFC
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SOURCE OF GAMMA RAYS New Class of Bewildering Gamma Ray Objects Discovered in Our Galaxy (G00-022) - The exotic world of gamma-ray astronomy has taken yet another surprising turn with the revelation that half of the previously unidentified gamma-ray sources in our own galaxy, the Milky Way, actually comprise a new class of mysterious objects. What objects could be emitting gamma rays? Possibilities are black holes acting as particle accelerators, the massive stars themselves, and clusters of oddball pulsars, among other theories.
ITEM (23) Mysterious Objects - Are Black Holes The Source? (G00-022-01) - Scientists think black holes in our galaxy could be a source of the mysterious gamma-rays. When black holes swallow large amounts of matter, they are sloppy eaters, often ejecting jets of material from their poles at high speed. This process is poorly understood, but the gamma rays are produced by high speed collisions between particles in the jets.
CREDIT: NASA/GSFC
ITEM (24) Mysterious Objects - The Case For Neutron Stars (G00-022-02) - Some scientists believe neutron stars in our galaxy could be a source of the mysterious gamma-ray glows. Scientists think the intense magnetic fields generated by the rapidly spinning star could project gamma rays, represented by the blue beams projecting from the star's poles.
CREDIT: NASA/GSFC
ITEM (25) Egret All-Sky Map (G00-022-04) - This image shows all 271 known sources of gamma-ray emitting objects. Gamma-rays are a type of highly energetic light invisible to the human eye. The false color represents intensity; large white areas glow more brightly in gamma rays than small orange ones. The image was captured by the Energetic Gamma Ray Telescope Experiment (EGRET) aboard NASA's Compton Gamma Ray Observatory (CGRO) spacecraft.
CREDIT: NASA/GSFC
ITEM (26) Location of Mysterious Objects(G00-022-05) - This image shows only the unidentified gamma-ray objects in our galaxy. Of the 120 unidentified sources in our galaxy, about half lie in a narrow band along the Milky Way plane. These may be well-known classes of objects that simply shine too faintly in other types of light to identify. The other half of the unidentified galactic sources are closer to Earth and make up the new class of mystery objects. These lie just off the Milky Way plane and seemingly follow the Gould Belt, a ribbon of nearby massive stars and gas clouds that winds through the Milky Way plane.
CREDIT: NASA/GSFC
ITEM (27) All Sky Animation (G00-022-06) - This animation begins with a look at our galaxy and dissolves to the Egret map showing all known gamma-0ray sources. The horizontal band is the galactic spirals seen edge-on, and the bulge is the galactic center. The sequence ends with the image showing the location of the mysterious sources.
CREDIT: NASA/GSFC
NASA Satellite Sheds Light Into The Most Cataclysmic Explosions in The Universe (G01-A031) - A rare optical afterglow of a gamma-ray burst, the most powerful type of cataclysmic explosion in the universe, was recently discovered by NASA's High-Energy Transient Explorer 2 (HETE-2), the first satellite dedicated to spotting these frequent yet random explosion that last only for a few seconds. This particular gamma ray burst occurred Sept. 21, 2001 in the constellation Lacerta, and was relatively close, only about 5 billion light years from Earth. HETE-2 pinpointed the exact location of a gamma ray burst in real time and instantly alerted other observatories to the burst. On the ground, a dozen listen-only burst alert stations relayed the data to the Massachusetts Institute of Technology (MIT) control center. In ten to 20 seconds, the information was sent to observatories worldwide including the Italian BeppoSAX satellite and the Ulysses space probe.PRE>
ITEM (28) Gamma Ray Burst Animation (G01-A031-01) - Gamma ray bursts are extraordinary high-energy emissions that could be triggered by the most exotic events found in the universe such as the birth of black holes, the explosive collapse of ordinary stars, or the collision of charged particles spewed by fierce stellar winds. They can occur several times a day without warning and typically last a few seconds before fading. The opportunity to see the afterglow in optical light provides crucial information about what is triggering these mysterious bursts. Because the enigmatic bursts disappear so quickly, scientists can best study the events by their afterglow. HETE detects these bursts as gamma rays or high-energy X rays, and then instantly relays the coordinates to a network of ground-based and orbiting telescopes for follow-up searches for such afterglows.
CREDIT: NASA/GSFC
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SOURCE OF ANTIMATTER:
Antimatter Surprises Scientists (G97-016/G97-103) - Scientists using data obtained by instruments on NASA's Compton Gamma Ray Observatory discover a unexpected cloud of antimatter near the galactic center.
ITEM (29) Antimatter Cloud in The Milky Way (G97-016-01) - Animation showing location of antimatter cloud observed by Compton Gamma Ray Observatory.
CREDIT: NASA/GSFC
ITEM (30) Antimatter Annihilation Animation (G97-016-02) - Animation demonstrates the intense amount of gamma ray radiation emitted when a positron (an antimatter electron) and an electron collide.
CREDIT: NASA/GSFC
ITEM (31) Antimatter Sources (G97-016-03) - Possible sources of this antimatter cloud above the center of the Milky Way galaxy. Possible sources include: a black hole emitting antimatter in a jet, a remnant of a gamma ray burst at the center of our galaxy, or super nova events near the center of the Milky Way galaxy. (INCLUDE: black hole animation with jet, gamma ray burst animation, and super nova animation)
CREDIT: NASA/GSFC |
| THE SPACECRAFT:
ITEM (32) Chandra Deploy Animation (G00-003-02) - The Chandra X-ray Observatory was launched by astronauts during the STS-93 mission at 7:47am EDT on July 23, 1999.
CREDIT: NASA/MSFC
ITEM (33) NASA'S Compton Gamma Ray Observatory (CGRO) Spacecraft (G00-022-07) - Compton was launched aboard the Space Shuttle Atlantis in April, 1991, and at 17 tons, it was the largest astrophysical payload ever flown at that time.
CREDIT: NASA/GSFC
ITEM (34) High-Energy Transient Explorer 2 (HETE-2) Animation (G01-A031-02) - A key feature of HETE-2 is its superior response time. When HETE-2 alerts other spacecraft to a gamma ray burst, they are able to see the afterglow of the burst (similar to a cinder slowly fading). HETE-2's ability to relay the accurate location of each burst in real-time to space and ground-based optical and radio observatories has the ability to revolutionize the area of high-energy astrophysics. HETE-2 was launched on October 9, 2000 from the Kwajalein Missile Range in the Marshall Islands.
CREDIT: NASA/GSFC
ITEM (35) Hubble Space Telescope Animation (G02-001-01) - Launched on April 24, 1990, NASA's Hubble Space Telescope was designed to be the most powerful astronomical observatory ever built. The keys to Hubble's power are its operation in space, far above the interference of the Earth's atmosphere, and to the unique instruments it carries as it orbits the planet. In addition, HST was the first observatory designed for extensive on-orbit maintenance and refurbishment.
CREDIT: NASA/GSFC
ITEM (36) Rossi X-Ray Timing Explorer (RXTE) Spacecraft (G98-001-02) - Animation depicting the RXTE studying X-ray emissions.
CREDIT: NASA/GSFC
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Space Science Gallery