By Marc Rayman
As NASA’s Dawn spacecraft makes its journey to its second target, the dwarf planet Ceres, Marc Rayman, Dawn’s chief engineer, shares a monthly update on the mission’s progress.
This illustration shows landmarks on Dawn’s voyage. After leaving Earth, the spacecraft flew past Mars to the giant protoplanet Vesta, where it spent 14 months in orbit. Now it is on its way to orbit dwarf planet Ceres. Image credit: NASA/JPL
On the seventh anniversary of embarking upon its extraordinary extraterrestrial expedition, the Dawn spacecraft is far from the planet where its journey began. While Earth has completed its repetitive loops around the sun seven times, its ambassador to the cosmos has had a much more varied itinerary. On most of its anniversaries, including this one, it reshapes its orbit around the sun, aiming for some of the last uncharted worlds in the inner solar system. (It also zipped past the oft-visited Mars, robbing the red planet of some of its orbital energy to help fling the spacecraft on to the more distant main asteroid belt.) It spent its fourth anniversary exploring the giant protoplanet Vesta, the second most massive object in the asteroid belt, revealing ...