Star And Planet Formation, a Dynamic View | Scott Wolk (SAO-Harvard Center for Astrophysics – USA)

Active star formation was originally identified by optical variability. Nonetheless constraints on telescope time and limitations in capability generally limited observations of young stars to single spectral observations and optical photometric monitoring. This has led to our current picture of star formation of rotating spotted star surrounded by a static disk. I discuss recent near and mid infrared observations which demonstrate that the disk is highly dynamic with periodic structure which appear to be related with both stellar rotation and circumstellar revolutionary times scales. In our JHK study of Orion we find periods for hundreds of Class I and Class II objects and demonstrate complex changes in disk structure. Mid-IR observations show significant variability as well. Finally I discuss the first X-ray observation of a planetary transit. We demonstrate the X-ray radius is significantly greater than the optical extent.