2000 SPACE SCIENCE VIDEOTAPES |
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Tape Title | Record ID | Date Produced | TRT: |
Synopsis |
| NEW CLASS OF BEWILDERING GAMMA RAY OBJECTS DISCOVERED IN OUR GALAXY
| G00-022 | 03/22/00 | 00:04:52 | 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. |
TAPE CONTENTS: |
| ITEM (1): Mysterious Objects - Are Black Holes the Source? - 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. |
| ITEM (2): Mysterious Objects - The Case for Neutron Stars - 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.
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| ITEM (3): Mysterious Objects - Stellar Winds As Possible Source - This animation illustrates how "winds" from massive stars in our galaxy could be a source of mysterious gamma-ray glows near the galactic plane. A star (red, orange and yellow sphere) ten to twenty times more massive than our Sun throws a continuous stream of electrically charged gas from its
surface at high speeds (orange cloud surrounding the star). This gas slams into gas atoms surrounding the star to produce gamma rays.
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| ITEM (4): Egret All-Sky Map - 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.
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| ITEM (5): Location of Mysterious Objects - 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.
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| ITEM (6): All Sky Animation - 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.
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| ITEM (7): NASA's Compton Gamma Ray Observatory (CGRO) Spacecraft - 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.
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