disks

Protoplanetary disks are rotating disks of gas and dust that surround young stars. They are believed to be the birthplace of planets, and are composed of the material left over from the star's formation. The material in these disks is thought to eventually form into planets, asteroids, comets, and other bodies. Protoplanetary disks can be observed with telescopes such as the Hubble Space Telescope and ALMA (Atacama Large Millimeter/submillimeter Array).