SEVEN DAYS

摘要

NASA's Dawn spacecraft slipped into the gravitational pull of Ceres on 6 March, making it the first probe to visit a dwarf planet. At nearly 1,000 kilometres across, Ceres, located in the asteroid belt, is one of the largest unexplored worlds in the Solar System. Dawn will orbit Ceres for the next 15 months, gathering information about the large amounts of water thought to lurk within the asteroid. The craft also visited the asteroid Vestain2011-12;its arrival at Ceres also makes Dawn the first probe to have orbited two celestial bodies. See go.nature. com/uwg9fb for more.