Dr. Mike Liu
U. Hawaii

University of Florida Astronomy Colloquium - May 26th, 2006

Young Circumstellar Disks: Substellar and Debris

We discuss two emerging areas which are furthering our understanding of disk evolution and its connection to the plausible diversity of planetary systems. (1) Disks around young brown dwarfs are now known to be as common as disks around young stars. We discuss the characteristics of these "circum-substellar" disks, including their potential for planet formation, and implications for the origins of brown dwarfs. (2) The transition from primordial disks to debris disks is intimately associated with the formation of planetesimals and planets. We present results from sub-mm and IR studies during the crucial 10-100 Myr epoch. We highlight the newly discovered disk around the nearby M star AU Mic, the first large scattered-light disk discovered in 20 years, and discuss its connections to other known young debris disk systems, including the long-studied archetype beta Pictoris.