Posted: Wed, Jan 9, 2013, 9:27 AM ET (1427 GMT)

Astronomers this week reported the discovery of several stars that have comets orbiting them, suggesting that cometary systems may be just as common as extrasolar planets. Researchers detected these "exocomets" by observing a telltale absorption line in spectra of six young A-class stars. That absorption line is created when an exocomet plunges into a star and evaporates. Astronomers believe that these stars likely also have planets that perturbed the orbits of the comets into the stars.