Jun 11 2008
From The Space Library
NASA successfully launched its Gamma-Ray Large Area Telescope (GLAST) aboard a Delta-2 rocket from Cape Canaveral Air Force Station]] at 16:05 (UT). GLAST could survey the entire sky every 3 hours, searching for gamma-ray bursts (GRBs). Scientists hoped to study GRBs to further their understanding of black holes, dark matter, and the laws of physics. GLAST consisted of two elements: the Gamma-Ray Burst Monitor (GBM) and the Large Area Telescope (LAT). The GBM was able to detect gamma-ray bursts and to orient the LAT to observe them more closely. NASA, the U.S. Department of Energy, and 37 other research institutions worldwide were collaborating on the US$690 million spacecraft.
Spacewarn Bulletin, no. 656, 1 July 2008, http://nssdc.gsfc.nasa.gov/spacewarn/spx656.html (accessed 24 April 2011); NASA, “NASA’s GLAST Launch Successful,” news release 08-141, 11 June 2008, http://www.nasa.gov/home/hqnews/2008/jun/HQ_08141_GLAST_Launch.html (accessed 21 April 2011); Dennis Overbye, “NASA Launches an Orbiting Mystery-Solver,” New York Times, 12 June 2008.
The International Astronomical Union (IAU) announced at a meeting in Oslo, Norway, that it would henceforth use the term “plutoid” to classify objects similar to Pluto. Astronomers had formerly believed that Pluto was a planet, but in 2006 the IAU had determined that Pluto was more accurately classified as an “object.” The 2003 discovery of an object both bigger and farther from the Sun than Pluto, in an area known as the Kuiper Belt, had precipitated the controversial decision to change Pluto’s status. Astronomers had named the newly discovered object Eris. Since that discovery, astronomers had adopted a number of terms to describe Pluto and Eris, including “dwarf planet,” “Kuiper Belt object,” and “plutino.” The IAU’s choice of the word “plutoid” was meant to quell the confusion. The IAU defined “plutoids” as “celestial bodies in orbit around the Sun at a distance greater than that of Neptune that have sufficient mass for the self-gravity to overcome rigid body forces so that they assume a hydrostatic equilibrium (near-spherical) shape, and that have not cleared the neighborhood around their orbit.” However, although Pluto and Eris fit this definition, the object Ceres, which is located between Mars and Jupiter, did not qualify for the status of “plutoid.” The IAU stated that it expected that astronomers would discover more plutoids in the future. Since the early twentieth century, the IAU had been officially responsible for naming astronomical bodies. However, some astronomers expressed their opposition to the term “plutoid” and to the IAU’s decision-making process in selecting the name.
Robert Roy Britt, “Pluto Now Called a Plutoid,” Space.com, 11 June 2008, http://www.space.com/5494-plutocalled-plutoid.html (accessed 29 April 2011).
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