Last week I meant to include an elegiac post to Rosetta, an astonishing space mission, which stretched out over a dozen years and logged 4.9 billion miles of travel. Rosetta was launched way back in 2004. It was originally supposed to rendezvous with comet 46P/Wirtanen in 2011, but problems with the launch in Guyana caused the probe to miss the launch window for the primary mission. The ESA changed the mission parameters so that the spacecraft ended up exploring Comet 67P/Churyumov–Gerasimenko instead (this second comet was functionally the same as the first—except for a much more difficult-to-say name). During its journey to the comet, Rosetta also flew by Mars and two asteroids. After flying by Mars in February of 2007, the craft flew by Earth in November of 2007. It caused a miniature panic when astronomers of the Catalina sky survey spotted it and misidentified it as a 20 meter near-Earth asteroid on a possible collision path with Earth!
The spacecraft arrived at Comet 67P/Churyumov–Gerasimenko in August of 2014 and the most famous…and infamous…part of the mission took place in November of that same year, when Rosetta launched the Philae lander to harpoon itself to the comet. Although Philae (which was named after a Rosetta-like obelisk with the same text in Greek and Egyptian) succeeded in landing and not bouncing off into the void, sadly the little lander came down in a miserable crevasse. Scientists intimately studied pictures of the comet (from Rosetta) until they found the lander in the icy chaos. It was a pretty ghastly scene which reminded me of my sock drawer (if it were dropped from space onto Tungnafellsjökull glacier).
(See it there at bottom right?)
Rosetta’s long and mostly successful mission came to an end last Friday in a truly operatic fashion. Mission controllers chose to use the last vestiges of power to smash the orbiter into the comet! Well, although I am saying “smashed” what actually happened was more like a grandmother walking into a snowbank. The lander was lowered onto the comet at about one mile per hour. Except, despite the fact that Rosetta traveled more than 5 billion miles (“uphill both ways”) it was not designed for landing and its last communication was a photo just above the comet surface. RIP Rosetta, you were one good probe!