Three-color image of the sky around TWA 30, with the faint red companion TWA 30B indicated due north.
Earlier this year, U. Hawaii Graduate student Dagny Looper reported the discovery of a young, low-mass and highly active star in the TW Hydrae Association, TWA 30. She has now found that that star is just one component of an unusual pair.
Only 80″ (0.02 degrees) north of TWA 30 lies a faint red star just barely visible in the image above. This source is so red that it was worth a look with the MagE spectrograph at the Magellan Telescopes. The resulting spectrum revealed a rich set of the same forbidden emission lines the we saw in the spectrum of TWA 30, indicating accretion onto the star from a circumstellar disk and powerful magnetically-driven jets emanating from the star’s poles. Moreover, we found two lines of forbidden neutral carbon emission, [C I], an important probe of the gas in the disk that surrounds this source, according to a 2009 study led by Dr. Barbara Ercolano. This is the first time these lines have been seen in the spectrum of a young star.
