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Space + FlightSpace & Flight

Decade-long Quest to Land on a Comet Comes to an End

ByTim De Chant, Allison EckNOVA NextNOVA Next
comet-image_1024x576
Philae planned to land in the red area, but ended up somewhere in the blue diamond.

This post has been updated.

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A box of metal and electronics cruising at 34,400 miles per hour is on the cusp of ending a decade-long quest to softly settle on the surface of a speeding comet. Rosetta, the European Space Agency’s comet orbiter, has dispatched the lander Philae, a 220-pound marvel that has just 64 hours to conduct experiments on the comet’s surface before its batteries will need a recharge.

The ESA launched Rosetta back in March 2004 to rendezvous with comet 67P/Churyumov-Gerasimenko, and the spacecraft’s day has finally come. If all goes well, Philae will touch down on the 2.5-mile-wide comet in a soft, boulder-free region. If the icy body doesn’t throw off too much dust and debris, the lander will recharge its batteries using its solar panels and continue working away until March, when scientists anticipate the comet’s temperature will rise beyond operating limits. We’ll be watching Philae’s every move, and you can, too, in the live stream below. Check back for updates.

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Update, 9:20 EST: Philae has sent back its first photo. You can clearly see its solar panels, which it will use to recharge its batteries.

. @philae2014 ’s first postcard just after separation – it’s of me! #CometLanding Credit: ESA/Rosetta/Philae/CIVA

pic.twitter.com/OXJwGunL3V

— ESA Rosetta Mission (@ESA_Rosetta) November 12, 2014

Update, 9:54 EST: Rosetta has spotted Philae with landing gear deployed. See all three images here .

I see you too @philae2014 ! Here you are in my OSIRIS camera – legs out! #CometLanding pic.twitter.com/hmnfe2AkN2 — ESA Rosetta Mission (@ESA_Rosetta) November 12, 2014

Update, 10:30 EST: Philae Lander Manager Stephan Ulamec says that in principle, the comet landing could happen at anytime now, possibly 10:35 EST. Confirmation signal expected at 11:02 EST.

Update, 11:03 EST: ESA receiving signals from Philae lander on surface of 67P/Churyumov-Gerasimenko — Touchdown!

RECEIPT OF SIGNAL FROM SURFACE European Space Agency receiving signals from @Philae2014 on surface of comet #67P /CG #cometlanding

— ESA Operations (@esaoperations) November 12, 2014

Update, 11:46 EST: ESA reports that harpoons didn’t fire as they’d thought. The team is looking into refiring options.

More analysis of @Philae2014 telemetry indicates harpoons did not fire as 1st thought. Lander in gr8 shape. Team looking at refire options — ESA Operations (@esaoperations) November 12, 2014

Update, 12:59 EST: Philae’s touchdown seen from its camera.

Great shot! MT @Philae2014 : . @ESA_Rosetta See for yourself! ROLIS imaged #67P just 3km away! #CometLanding pic.twitter.com/1FwWs1tioF

— ESA Rosetta Mission (@ESA_Rosetta) November 12, 2014

Update, 2:28 EST: Check out the Flickr photos of Philae’s landing on 67P. If you missed the final media briefing of the day, there will be another one tomorrow at 8am EST. Check back here for the stream (same video player, above). Update, Nov. 13 9:51 a.m. EST: Philae is on the surface of the comet, but it actually bounced several times to get where it is now. Currently, one of the lander’s three feet is suspended in space; the other two rest on the surface despite the harpoon system’s failure to launch. In addition, Philae is hiding in the shadow of cliff about a kilometer away from the planned landing site, limiting the amount of sunlight available for the lander to use in recharging its batteries. If Philae can’t recharge, it’ll only have about 64 hours (from the time of touchdown) to conduct experiments.

Now that I’m safely on the ground, here is what my new home #67P looks like from where I am. #CometLanding pic.twitter.com/gFmt8Ldvpa — Philae Lander (@Philae2014) November 13, 2014

comet-image_1024x576
Philae planned to land in the red area, but ended up somewhere in the blue diamond.

ESA scientists say they are wary of giving the harpoons a second go until they know exactly where Philae is and what the surrounding terrain looks like. Otherwise, a hasty attempt could catapult the lander back into space.

Update, Nov. 14 4:35 p.m. EST: ESA Operations reports that Philae has drilled 25 centimeters (10 inches) into the comet to start taking samples of the 4.5-billion-year-old material beneath its surface. Unfortunately, it doesn’t look like the lander has much time left; its batteries are draining, and without direct access to sunlight, it can’t recharge its solar panels. Mission control is scheduled to make contact with Philae again overnight, but its power could be exhausted by then. If that’s the case, Philae will remain inert for the coming months while Rosetta continues to circle the comet. Nevertheless, scientists urge the public to acknowledge Rosetta’s successes thus far, rather than the few inevitable kinks along the way.

Update, Nov. 15: The ESA lost contact with Philae at 6:36 p.m. EST Nov. 14. The lander is now in “idle mode,” and it’s unlikely that communication will be reestablished in the near future. Philae could reawaken if sunlight manages to reach its solar panels. Before it went to sleep, though, it sent some data back that scientists hope could help solve the mysteries of our solar system’s birth.

Listing image: ESA/ATG medialab

Embedded image: ESA

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