Living and Dying With a Comet

Like many other space enthusiasts around the world, I woke up today in a bittersweet mood as I read the reports about the death of the European Space Agency's Rosetta comet probe. Its demise was carefully planned and long foretold but was sad all the same, putting a period at the end of a story that rolling out for more than 12 years. During that time, Rosetta made three passes by Earth, one by Mars, visited a pair of asteroids, and spent more than two years scrutinizing Comet 67P/Churyumov-