spacetoday.net: Astronomers detect gas streams linked to new planets

Posted: Thu, Jan 3, 2013, 7:46 AM ET (1246 GMT)
Protplanet gas streams illustration (ESO)

Radio astronomers announced Wednesday that they have detected for the first time streams of gas flowing into a star created by the formation of new planets. Astronomers detected the gas streams around HD 142527, a star 450 light-years from the Earth, in observations by the ALMA radio telescope array in Chile. The streams of gas come are drawn from an outer protoplanetary disk surrounding the star by gas giant planets that formed in a gap between that outer disk and the inner one. Some of the material in the streams are captured by the new planets, but much of it continues to flow inward to the inner disk, replenishing it as the star itself grows. The development of these gas streams had been predicted by models of planetary formation, but had not been directly observed before now. The findings appear in the latest issue of the journal Nature.