Sep 17 2002
From The Space Library
Observations from the HST revealed the existence of medium-sized black holes. According to scientists, the discovery provided important information about the creation of many types of celestial bodies. Scientists were surprised to find that the black holes in the cores of globular star clusters~bright clusters of stars that orbit galaxies, including the Milky Way~are nearly 10,000 times less massive than galaxies. The HST data revealed that black holes in globular star clusters are proportionally smaller than massive black holes found in galaxies, demonstrating that the mass of a black hole is proportional to its stellar surroundings. The results also indicated that when the globular star clusters had formed they had black holes, suggesting that, to form large star clusters, black holes must act as gravitational anchors. Scientists believed these findings might illuminate the process by which galaxies and globular clusters formed. The discovery also suggested that black holes are more ubiquitous than scientists had previously thought. (NASA, “Hubble Discovers Black Holes in Unexpected Places,” news release 02-174, 17 September 2002; William Harwood, “Finding May Connect Dots on How Galaxies Form; Mid-size Black Holes Are Discovered,” Washington Post, 18 September 2002.)
The GAO submitted a report to the House Science Subcommittee on Space and Aeronautics on NASA's progress toward developing a reusable launch vehicle (RLV), under the Space Launch Initiative (SLI) program, to replace the Space Shuttle. According to GAO, NASA needed to complete ongoing reassessment of its overall space transportation plans and of the future of the ISS. NASA also needed to determine whether it would develop the SLI program in cooperation with the DOD. To address these concerns, GAO recommended that NASA reassess the schedule for defining the SLI's requirements and reach a consensus with the DOD on the program's priorities and objectives. The report also recommended that NASA finalize the SLI's basic requirements before implementing management controls on the program's costs and risks. In its response, NASA concurred with GAO's recommendations and outlined plans to implement them. (U.S. General Accounting Office, “Space Transportation: Challenges Facing NASA's Space Launch Initiative” (report no. GAO-02-1020, Washington, DC, 17 September 2002), http://www.gao.gov/new.items/d021020.pdf (accessed 10 October 2008).)
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