Aug 1 2002
From The Space Library
The U.S. Senate confirmed Frederick D. Gregory as NASA's Deputy Administrator, making Gregory the first African American to serve as NASA's second-in-command. Before becoming Deputy Administrator, Gregory had served as NASA's Associate Administrator for Space Flight from December 2001 to August 2002 and as Associate Administrator for the Office of Safety and Mission Assurance from June 1992 to December 2001. In addition, Gregory had been an astronaut on three Shuttle missions and had served in the U.S. Air Force for 30 years. (Kelly Young, “Senate Names New NASA Official,” Florida Today (Brevard, FL), 3 August 2002; NASA, “NASA Deputy Administrator Frederick D. Gregory,” http://www.nasa.gov/about/highlights/gregory_bio.html (accessed 26 September 2008).)
Analyzing observations of the dwarf galaxy NGC 1569, a group of astronomers led by Crystal L. Martin of the University of California Santa Barbara found the first evidence that such galaxies produce most of the heavy elements in the universe. Heavy elements, defined as all elements other than hydrogen and helium, are essential for planet formation and can strongly influence astronomical phenomena such as the rate of galaxy formation. Scientists had theorized that, during the early development of the universe, heavy elements emanating from dwarf galaxies played a dominant role in enriching the intergalactic gas that formed other galaxies. Data from NASA's Chandra X-ray Observatory enabled Martin and her team to test this idea. They found that NGC 1569 emitted large quantities of heavy elements in extremely hot x-ray winds, the first direct evidence of metal-enriched winds from dwarf galaxies. The researchers noted that the findings left open the question of whether or not dwarf galaxies or other galaxies dominate the intergalactic metallic enrichment process. (NASA, “Dwarf Galaxies Give Universe a Breath of Fresh Oxygen,” news release 02-134, 23 July 2002; Crystal L. Martin, Henry A. Kobulnicky, and Timothy M. Heckman, “The Metal Content of Dwarf Starburst Winds: Results from Chandra Observations of NGC 1569,” Astrophysical Journal 574, no. 2 (1 August 2002): 663-692.)
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