'Out, damned spot.' (spot observed next to supernova 1987 disappears)"Out, damned spot' The incriminating in·crim·i·nate tr.v. in·crim·i·nat·ed, in·crim·i·nat·ing, in·crim·i·nates 1. To accuse of a crime or other wrongful act. 2. spot that Lady Macbeth Lady Macbeth while sleepwalking, discloses her terrible deeds. [Br. Drama: Shakespeare Macbeth] See : Sleep wanted to be rid of would not disappear. The spot that has perplexed astronomers lately--and been damned by some of them--seems to have disappeared, but its discoverers say it could come back again. This is the strange "companion' to the supernova supernova, a massive star in the latter stages of stellar evolution that suddenly contracts and then explodes, increasing its energy output as much as a billionfold. 1987A, the bright object that suddenly appeared next to the supernova itself (SN:8/22/87, p.122). The leader of the group that discovered the spot, Costas Papaliolios of the Harvard-Smithsonian Center for Astrophysics The Harvard-Smithsonian Center for Astrophysics (CfA) is located in Cambridge, Massachusetts. It consists of the Harvard College Observatory and the Smithsonian Astrophysical Observatory. The Center is located at 60 Garden Street. in Cambridge, Mass., says that although the spot had appeared in observations taken on March 25 and April 2, it was not present in observations on May 30 and June 2. At least one member of the audience, Nolan Walborn of the Goddard Space Flight Center The Goddard Space Flight Center (GSFC) is a major NASA space research laboratory established on May 1, 1959 as NASA's first space flight center. GSFC employs approximately 10,000 civil servants and contractors, and is located approximately 6.5 miles northeast of Washington, D.C. in Greenbelt, Md., expressed doubt about the existence of the spot at any time. However, others expressed confidence in Papaliolios's observational technique. Known as speckle Speckle The generation of a random intensity distribution, called a speckle pattern, when light from a highly coherent source, such as a laser, is scattered by a rough surface or inhomogeneous medium. interferometry, the technique uses computer analysis of thousands of images taken through a mask with seven pinholes. Scientists look for correlations that reveal details that turbulence in the atmosphere normally blurs. Papaliolios maintains that the earlier observations were not spurious. The spot was really there, he says. It may have faded, or the location of the supernova during the May-June observations, which was much closer to the horizon than earlier in the year, may have made the spot harder to see. The group is currently analyzing observations made later in the summer to see whether the spot reappears. |
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