Discovery of a Wacko Star

Jets, disks and accretion in nearby low mass star

U. Hawaii Graduate student Dagny Looper reports the discovery of a young, low-mass nearby star that is both unusually active and highly variable. The star, TWA 30, is a member of the TW Hydrae Association, roughly two dozen ~8 million year-old stars located about 50 pc away. TWA 30 is the newest member of this group, and one of the most intriguing. Its optical spectrum shows classical and forbidden emission lines, indicating that it is both accreting material and emitting high-speed jets of gas. The star’s near-infrared color also varies dramatically on week-long timescales, evidence that it periodically hides behind a nearly edge-on circumstellar disk. This makes TWA 30 one of the nearest T Tauri stars to the Sun.

The paper was published in the Astrophysical Journal.

May 2010