A debris disk is a ring of dust and small particles that orbits a star, often found around young stars. These disks are formed from leftover material that did not coalesce into planets during the star's formation. The debris can include ice, rock, and other materials, and it can provide valuable insights into the processes of planetary formation. Debris disks are often studied using telescopes, such as the Hubble Space Telescope and the Atacama Large Millimeter/submillimeter Array (ALMA). Observing these disks helps astronomers understand the evolution of planetary systems and the conditions that lead to the formation of planets like Earth.