spacetoday.net: Brown dwarf, disk discoveries could lead to exoplanet images

Posted: Tue, Jan 8, 2002, 8:24 AM ET (1324 GMT)
Brown dwarf orbiting 15 Sge (M. Liu)

Images of a brown dwarf orbiting a Sunlike star and a protoplanetary disk around a young star could be key steps towards the first direct images of an extrasolar planet, astronomers said Monday. One team of astronomers reported that they had taken images of a brown dwarf orbiting just 14 AUs (2.1 billion km) from its parent star, 15 Sge, 58 light-years from the Earth. The brown dwarf, up to 78 times the mass of Jupiter, is the closest brown dwarf to a star directly observed. Another team reported the discovery of a protoplanetary disk around a star just two million years old in a cluster 900 light-years from the Earth. Both discoveries were made with adaptive optics systems, which correct for the distortions in images created by the Earth's atmosphere, on some of the world's largest telescopes, the 8-meter Gemini North and 10-meter Keck 2. Astronomers believe it is now possible to use such telescopes to directly observe gas giant planets the size of Jupiter, provided they are young planets still hot and thus bright at infrared wavelengths. Such discoveries could come within the next 6 to 18 months. The two discoveries were announced at a meeting of the American Astronomical Society in Washington, DC.