[meteorite-list] Philae Lander Fails to Respond to Last-Ditch Efforts to Wake It

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Wed, 13 Jan 2016 16:25:28 -0800 (PST)
Message-ID: <201601140025.u0E0PS0g009848_at_zagami.jpl.nasa.gov>

https://www.newscientist.com/article/dn28752-philae-lander-fails-to-respond-to-last-ditch-efforts-to-wake-it/

Philae lander fails to respond to last-ditch efforts to wake it
New Scientist
By Jacob Aron
11 January 2016

Farewell, Philae. The space lander that touched down on comet 67P/Churyumov-Gerasimenko
(and in our hearts) in November 2014 has not responded to a last-ditch
attempt to wake it, and it now looks almost certain that the lander is
permanently sleeping.

Comet 67P is moving away from the sun, and in just a few weeks will become
too cold and dim for the lander to survive. It has not been heard from
since July 2015. Last night, mission managers at the German Aerospace
Center in Cologne sent a signal to Philae commanding it to spin its internal
flywheel, a risky and unpredictable manoeuvre that could dislodge it from
its shady landing spot in the hope of getting more sunlight on its solar
panels. It didn't work.

"We did not hear anything," says lander manager Stephan Ulamec. In the
best-case scenario, Philae may have received the command and moved, but
be unable to respond due to a damaged transmitter. It is more likely that
the signal was not received.

In mourning

The team will try a few more commands, but it looks like Philae has officially
gone. "We have to face reality, and chances get less and less every day
as we are getting farther and farther away from the sun," says Ulamec.
'At some point we have to accept we will not get signals from Philae anymore."

Philae's orbiting companion Rosetta has scanned the landing zone with
its camera. Ulamec's team will scour the images for any sign of a dust
cloud thrown up by the lander moving, but Rosetta is far away from the
comet and Philae is too small to be seen directly.

Besides mourning the loss of the most famous space probe of recent times,
the team is also disappointed that Philae may have more data about 67P
stored in its memory that will now be lost. 'It's certainly a bit sad
that we could not retrieve more data after the wake-up in June," says
Ulamec. 'We have to live with the data that we got in November 2014."

There remains one small hope. As Rosetta comes to the end of its mission
in September this year, mission managers are planning to bring it down
into a very low orbit of the comet, eventually touching down on the surface
itself. Rosetta should be able to capture close-ups of Philae's final
resting spot, giving us one last look at the probe. "You should clearly
see the lander, and this will help us interpret the data we received in
November," says Ulamec.
Received on Wed 13 Jan 2016 07:25:28 PM PST