Philae comet lander awakes from hibernation

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This is interesting information on the ESA Philae Comet Lander that has been asleep on the comet since mid November 2014. It has now made contact and is now "awake"!

Jane Onyanga-Omara, USA TODAY 10:17 a.m. EDT June 14, 2015

The European Space Agency's probe Philae has woken up and contacted Earth after about seven months in hibernation, the organization said Sunday.

It said the European Space Operations Center in Darmstadt, Germany, received signals from the lander late Saturday.

Scientists lost connection with the solar-powered probe after it was dropped on comet 67P/Churyumov-Gerasimenko by its mothership Rosetta on Nov. 15.

Philae's battery ran out of around 60 hours after it landed next to a cliff that largely blocked sunlight from reaching its solar panels.


More: http://www.usatoday.com/story/news/world/2015/06/14/philae-lander-space-probe/71207006/

[rdunk]

Another today's news article gives us more detailed information about this lander, and the Spacecraft that delivered it. Just recently ESA received relayed images from the Rosetta Spacecraft which possibly gives some information on the lander's location on the comet.

It does seem that the writer of this article did not yet know that Philae was now awake!


Perfect Science - Submitted by Safar Haddad on Sun, 06/14/2015 - 01:21 - See more at:

Recent images relayed by the European Space Agency's Rosetta Spacecraft, have zeroed in on the current possible location of the lost robotic probe Philae lander, which left the Earth in November 2014, to land on Comet 67P/Churyumov-Gerasimenko.

The space probe is approximately 309 million km away from the Earth and around 218 million km from the Sun. It did land onto the desired comet, however, it probably settled at a shady area, after swirling across the dusty surface of the comet. Due to this, the lander got cut off from sunlight, in the absence of which, it would not have been able to recharge its batteries. Therefore, it fell silent, though it did conduct a fast scan of the comet's environment prior to that.

However, the astronomers opine that the lander may revive if the comet's orientation chances and greater sunlight falls on the lander's solar panels.


- See more at: http://perfscience.com/content/2142055-european-space-agency%E2%80%99s-rosetta-spacecraft-relays-images-lost-probe-philae-lander#sthash.QnPfJD1O.dpuf

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N° 20–2015: ROSETTA'S LANDER PHILAE WAKES UP FROM HIBERNATION

14 June 2015




Rosetta's lander Philae has woken up after seven months in hibernation on the surface of Comet 67P/Churyumov-Gerasimenko.

The signals were received at ESA's European Space Operations Centre in Darmstadt at 22:28 CEST on 13 June. More than 300 data packets have been analysed by the teams at the Lander Control Center at the German Aerospace Center (DLR).

"Philae is doing very well: It has an operating temperature of -35ºC and has 24 Watts available," explains DLR Philae Project Manager Dr. Stephan Ulamec. "The lander is ready for operations."

For 85 seconds Philae "spoke" with its team on ground, via Rosetta, in the first contact since going into hibernation in November.

When analysing the status data it became clear that Philae also must have been awake earlier: "We have also received historical data – so far, however, the lander had not been able to contact us earlier."

Now the scientists are waiting for the next contact. There are still more than 8000 data packets in Philae's mass memory which will give the DLR team information on what happened to the lander in the past few days on Comet 67P/Churyumov-Gerasimenko.

Philae shut down on 15 November 2014 at 1:15 CET after being in operation on the comet for about 60 hours. Since 12 March 2015 the communication unit on orbiter Rosetta was turned on to listen out for the lander.

Rosetta is an ESA mission with contributions from its Member States and NASA. Rosetta's Philae lander is contributed by a consortium led by DLR, MPS, CNES and ASI.

More information at: http://blogs.esa.int/rosetta/2015/06/14/rosettas-lander-philae-wakes-up-from-hibernation/

ESA PRESS RELEASE

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[zorgon]

Philae lander 'on its side and in the shade' - but scientists say the craft is perfectly operational



The Philae lander may be in trouble after scientists revealed that the probe was bounced hundreds of metres away from its designated landing site and is currently on its side at the foot of a cliff.

The spacecraft is in perfect operational order but engineers from the European Space Agency (ESA) have confirmed that it is "almost vertical" with "one foot in the open air".

"This has an impact on our energy budget," said one scientist. "The lander is relying on solar energy [and] we're getting one and half hours of sunlight when we expected six or seven."

Philae has enough power in its batteries to last for around sixty hours of operation, but scientists are hoping they might be able to move the craft to a more favourable position using the landing gear.

http://www.independent.co.uk/news/science/philae-lander-on-its-side-and-in-the-shade--but-scientists-say-the-craft-is-perfectly-operational-9858872.html

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Rosetta mission: why did Philae bounce?



As the dusts settles (quite literally) around the landing of the Philae probe, scientists have confirmed that craft didn't touch down just once – it actually bouncedon the surface of the comet twice.

But what's happening here? Since when did spacecraft bounce?

Well, it's all down to the comet's gravity. 67P/Churyumov-Gerasimenko may be an icy mass the size of a mountain, but gravity is an incredibly weak force (you overcome it every time you get out of bed in the morning) and it only really becomes noticeable with huge, planetary masses.

The comet's gravity is actually several hundred thousand times weaker than that on Earth and, to make matters worse, the uneven shape of the comet means that even this force varies over its surface.

Its gravity is so weak that scientists working on the Philae lander had to take account of the fact that even the slightest movement on the craft – say, adjusting a camera to look left or right – could be enough to lift it off the surface.

http://www.independent.co.uk/news/science/rosetta-mission-why-did-philae-bounce-9857771.html