By Ron Cowen
Astronomers have found what may be the heaviest, biggest, and brightest star ever observed. The star, known as LBV 1806-20, may weigh more than 150 times as much as the sun, span 200 times its width, and shine up to 40 million times as brightly.
Residing 45,000 light-years from Earth and blocked by dust, the star appears dim in visible light. But at the infrared wavelengths studied by Stephen S. Eikenberry of the University of Florida in Gainesville and his colleagues, about 10 percent of the star’s radiation penetrates the dust. Eikenberry reported the team’s finding on Jan. 6 in Atlanta at a meeting of the American Astronomical Society.
The researchers’ sharp infrared images and spectra have made determinations of the star’s distance, temperature, and infrared emissions that are more precise than ever before. These data, in turn, led to new estimates of LBV 1806-20’s properties.
Donald F. Figer of the Space Telescope Science Institute in Baltimore cautions that LBV 1806-20 could turn out to be two or three closely orbiting stars masquerading as a single bright body. In that case, says Eikenberry, the brightness of the star might at best rival the current record holder, a massive star called the Pistol that Figer’s team imaged in 1997 (SN: 10/11/97, p. 231).
Figer says that infrared spectra of LBV 1806-20 recently obtained by his group should reveal whether the body is a single star or several.
With both LBV 1806-20 and the Pistol discovered in the past decade, “other monster stars may still be lurking in the depths of the Milky Way,” Eikenberry notes, and some of them might even dwarf the current record holders.
****************
If you have a comment on this article that you would like considered for publication in Science News, send it to editors@sciencenews.org. Please include your name and location.
