Rosetta's 12-Year Mission Ends With Landing On Comet (sciencemag.org)

sciencehabit writes: It was an unusual grand finale. The crowded European Space Agency (ESA) operations center in Darmstadt, Germany, waited in silence and then the signal from the descending Rosetta mission simply stopped at 1.19 pm local time showing that the spacecraft had, presumably, landed on comet 67P/Churyumov-Gerasimenko some 40 minutes earlier, due to the time the signal takes to reach Earth. Mission controllers hugged each other; there was gentle applause from onlookers; and that was it. There were no last minute crises. Seven of Rosetta's instruments kept gathering data until the end. Holger Sierks, principal investigator of the 12-year mission's main camera, showed the gathered staff, officials, and journalists Rosetta's final picture: a rough gravelly surface with a few larger rocks covering an area 10 meters across. Earlier, it had snapped the interior of deep pits on the comet (shown above, from an altitude of 5.8 kilometers) that may show the building blocks it is made of. "It's very crude raw data but this will keep us busy," Sierks said. It is hoped that this last close-up data grab will help to clarify the many scientific questions raised by Rosetta.

Comments

Re:Meanwhile, the fucking Mars rover

[tlhIngan]

But why did they program it to shut off on impact? Who cares if it might be damaged and short-circuited by the impact, it's end of life anyway, might as well see if if some parts of it survive the impact and send back something useful. No, they intentionally programmed it to go into "safe mode" and basically shut off at the moment of impact. A "clean end" to the mission, they called it. I think they should have gone for some "dirty" pictures instead. Better than nothing, and what does the probe have to lose? It may have bounced around for hours with all its sensors shut off while it was still perfectly capable of sending back more data.

First off, Rosetta is not Philae. It was never designed to "land" - just orbit. The moment of impact it was going to be destroyed You have to remember that they're only strong when they were folded up - once everything's unfolded it's quite fragile. At the moment of landing, the solar panels would've collapsed - they are long parts and it was only strong when it was folded up for launch, so it would've twisted and bent.

And there's no power once that happens - Rosetta was dying - its onboard fuel is nearly depleted and its far from the sun so its power reserves are diminished. This lets it do some final science using its onboard sensors and relay some final data before impact.

Additionally, the antenna would've collapsed on impact so it will no longer be pointing towards earth so even if they kept Rosetta "on", there would be no way to receive anything because the antenna would be pointed in a random direction.