TRAPPIST-1 planets probably rich in water
A new study has found that planets orbiting the star TRAPPIST-1 are made mostly of rock, and some could hold more water than Earth. The planets’ densities suggest that some of them could have up to 5 percent of their mass in the form of water. The hotter planets closest to their parent star are likely to have dense steamy atmospheres and the more distant ones probably have icy surfaces. …read more