Scientists have found a planet about 4.5 times the mass of Earth that orbits in the heart of its star's habitable zone, with two other suns orbiting much farther away. Is there water or the potential for life? Perhaps. But the planet could also be a two-faced world of scorching sun and perpetual ice.
Extrasolar planet discoveries have boosted by 50 percent the number of known planets orbiting massive stars. Extrasolar planets are those outside of our solar system.