Stars with Dusty Disks Should Harbor Earth-like Worlds

Stars with disks of debris around them might be good targets to search for Earth-like planets, researchers say.

Debris disks consist of fields of planetesimals and dust encircling stars. A few hundred stars have been found that show signs of a debris disk, said astrophysicist Sean Raymond at the Observatory of Bordeaux in France.

The lifetime of dust is very short compared with that of stars — for instance, the dust can get scattered out into interstellar space by gravitational perturbations from giant planets. It is thought that any debris disks astronomers spot are replenished by collisions between asteroid-sized bodies that are basically leftovers of rocky planet formation. As such, if any disk that is seen is relatively large, it might suggest its system might be calm enough in terms of its orbital dynamics for rocky worlds to form.