Dec 23 2002
From The Space Library
NASA announced the backup crew members for ISS Expedition 10, including Jeffrey N. Williams, acting as backup for the ISS station commander, Russian cosmonaut Konstantin M. Kozeev, and U.S. astronaut Sunita L. Williams. The primary crew members for Expedition 10 were ISS Commander Leroy Chiao, U.S. astronaut John L. Phillips, and Russian cosmonaut Salizhan S. Sharipov. (NASA, “Space Station Expedition Backup Crew Named,” news release 02-258, 23 December 2002.)
With the aid of NASA's High Energy Transient Explorer (HETE), scientists were able to capture the first images ever taken of an unusual gamma-ray burst (GRB) that signals the birth of a new black hole. With the exception of the Big Bang, GRBs are the most powerful type of explosion known. The bursts last for only a few seconds, yet their afterglows can last for days or even longer. However, scientists had been unable to detect an optical afterglow produced by a fast-fading type of dark GRB~until the HETE indicated that such a burst was occurring. NASA had created the satellite to alert ground-based observatories to GRBs. On 11 December 2002, HETE had detected a GRB and, within 22 seconds, had notified observatories of the event's location. In the following minutes, ground-based telescopes captured images of the burst's afterglow, which disappeared in 2 hours. The event was a rare subcategory of dark GRBs known as a transitional burst~ a burst with an afterglow lasting longer than that of the short-duration type, but shorter than that of a long-duration burst. Moreover, these transitional bursts are the rarest type of GRB. Scientists hoped the images would help them learn more about the causes of GRB in general, as well as providing specific data indicating the reason that dark bursts have no detectable afterglow. (NASA, “Scientists Catch Their First Elusive 'Dark' Gamma-Ray Burst,” news release 02-257, 23 December 2002.)
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