Mar 14, 2013
John Tobin, NRAO
"From Filaments to Disks: Observing Solar System Formation"
The formation of proto-planetary disks begins during the earliest phase of the star formation process, while the nascent protostar is still surrounded by a dense envelope of gas and dust. We are beginning to have views of the entire star formation process from 1 pc all the way down to ~10 AU scales using a variety of observational techniques. 8 micron shadow images from Spitzer to show that the dense envelopes around Class 0 protostars are generally morphologically complex, often being filamentary and asymmetric. The observed envelope structure indicates a likely origin in turbulent cloud structure rather than a quasi-static formation and increase the likelihood of fragmentation during collapse, forming close binaries. With sub/millimeter interferometers, we can zoom in on the envelope and resolve forming proto-planetary disks around Class 0 protostars for the first time. Moreover, the rotation of the disks enables us to directly measure the mass of the protostar L1527 in Taurus.
Probing deeper, we also find that binaries are forming during the protostellar phase with 100 AU separations, a strong indication that the disks themselves are fragmenting early-on. This lays the ground work for ALMA, which will be needed to make significant gains in the area of disk formation with vastly improved resolution and sensitivity. Most importantly, ALMA's ability to detect faint molecular lines will enable masses of a large number of Class 0 protostars to be measured for the first time.