It took five loops around the Sun, three gravity-assist fly-bys of Earth and one of Mars, and a journey of 3.97 billion miles lasting 10 years, five months and four days. After all that, the Rosetta spacecraft finally reached it destination today — and made history.
Rosetta is the first spacecraft ever to rendezvous with a comet. It is now in quasi-orbit (more about that in a minute) around comet 67P/Churyumov-Gerasimenko. For more than a year, it will take pictures and gather data, and i