The potential effects of these changes on an organism's evolution "is a fascinating topic that we are just beginning to explore," Dr. Welsh notes.
Sounds too daunting for a vacation spot? Try planets around a red dwarf.
Another team reported discovering the smallest planets yet confirmed. One is roughly the size of Mars. The other two are smaller than Venus. All three orbit a dim red-dwarf star some 130 light-years from Earth. The star is only about 70 percent larger than Jupiter.
The planets are orbiting too close to the star to fall within its habitable zone. But the find is intriguing, nonetheless.
Red dwarfs represent some 80 percent of all the stars in the galaxy, says John Johnson, an astronomer at the California Institute of Technology and a member of the team reporting the discovery. If the discovered planets are any indication, he notes, red dwarf stars throughout the galaxy could be "swarming with little habitable planets."