61 Virginis is one of only a handful of truly Sun-like stars that can be seen with the naked eye. Astronomers have discovered three low-mass planets orbiting the star. NASA.

Paul Butler and a team of international planet hunters have discovered as many as six low-mass planets around two nearby Sun-like stars, including two “super-Earths” (the first found around Sun-like stars) with masses 5 and 7.5 times the mass of Earth. The team found the new planet systems by combining data gathered at the Keck Observatory and the Anglo-Australian Telescope (AAT). Two papers describing the new planets have been accepted for publication in the Astrophysical Journal.

According to Butler, the new discoveries required state-of-the-art instruments and detection techniques. "The inner planet of the 61 Vir system is among the two or three lowest-amplitude planetary signals that have been identified with confidence," he commented, "We've found there is a tremendous advantage to be gained from combining data from the AAT and Keck telescopes, two world-class observatories, and it's clear that we'll have an excellent shot at identifying potentially habitable planets around the very nearest stars within just a few years."

For more information, see the UC Santa Cruz Web site and the team's press Web site.