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Related: Editorials & Other Articles, Issue Forums, Alliance Forums, Region ForumsPhilae comet lander is in shadow of cliff, may have battery recharging problems
http://blogs.esa.int/rosetta/2014/11/13/philae-the-happy-lander/
From the recent press conference:
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The lander is relying on solar energy ... were getting one and half hours of sunlight when we expected six or seven. This has an impact on our energy budget.
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Stephan Ulamec explains that activating any moving parts will be high risk, tipping the lander or pushing it away from the surface completely: Drilling without being anchored is dangerous. The same applies to any attempt to fire the harpoons.
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Jean-Pierre Bibring, however, points out that drilling to take samples for isotopic analysis is critical to the whole scientific purpose of the mission. With time running out, he hopes that this might be given the green light as soon as tomorrow.
http://www.theguardian.com/science/across-the-universe/live/2014/nov/13/rosetta-mission-philae-lander-live-coverage-comet-esa
After showing an image that indicates Philae's location - on the far side of a large crater that was considered but rejected as a landing site - the head of the lander team Stefan Ulamec said: "We could be somewhere in the rim of this crater, which could explain this bizarre orientation that you have seen."
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In any event, it may have risen vertically or drifted sideways - we should hear later. Either way, while Philae was off the surface, the comet will have rotated beneath it. Each rotation takes about 12 hours which means the lander may effectively travelled across one-sixth of the comet's surface.
By the time it came down again, the original landing zone - chosen for its relative safety and ideal amount of sunshine - was left far behind. The lander is now in different, undetermined area that may prove far more hazardous.
The first picture is confusing, but suggests Philae is sitting at an angle. Everyone here is hungry for more news.
http://www.bbc.co.uk/news/science-environment-30034060
MannyGoldstein
(34,589 posts)To assume that where ever the thing touched down would be a good spot.
Perhaps tiny thrusters could have been added so the thing could jump around until it found a good spot.
Maybe I'm misunderstanding what's going on...
snooper2
(30,151 posts)muriel_volestrangler
(101,355 posts)The problem was they had a thruster designed to 'pin it down' when it landed, but they found, before it was released from Rosetta, that it appeared to have malfunctioned; they went ahead anyway (I don't know if they had an alternative). And the harpoons and ice screws didn't secure it (I wonder if deploying them may have been what got it to 'hop' away from the decent site - if they didn't 'bite', they may have pushed instead).
I suppose they could have designed it to have thrusters to try to move it around, but it's all extra mass for that, rather than scientific instruments, and it would all have to be run by the computer without input from Earth, since it's a hour round trip for the radio signals. They had to do the design without any pictures of what the comet is like, so it was all inspired guesswork anyway ...
Baclava
(12,047 posts)[IMG][/IMG]
Baclava
(12,047 posts)Without solar power it will die in 30 hours
Esa has confirmed they will make a daring attempt to save the Philae probe on the surface of comet 67P
According to Philippe Gaudon, who heads the Rosetta mission at the French space agency CNES, the probe is thought to be at an angle of about 30 degrees on the surface.
Eight of the ten instruments on board the spacecraft have also apparently taken data so far, but the solar panels seem to have been damaged during the dramatic landing.
The probe landed on the comet at around 3.30pm GMT yesterday but then bounced twice, first to a height of 0.62 miles (1km) and then to a much lower height before coming to rest. It is also thought to be about 0.62 miles (1km) from its intended landing site.
Esa confirmed in a statement that after the bounces rotated the probe around its vertical axis, which means it is now not upright on the comet.
This means that parts of the lander are in shadow but, they added: 'Nonetheless, the lander appears to be performing well.'
Philae only has around 20-30 hours of battery life in its main battery, before it will attempt to switch to rechargeable ones replenished by sunlight.
If it cannot get enough sunlight it will ultimately run out of power in at most 60 hours.
Mr Ferri says that all of the non-mechanical instruments on Philae are now working perfectly, but scientists will not be attempting to start up any of the mechanical instruments.
If we move something it might tip it over
once we know the attitude [angle], we will know what instruments we can use.
http://www.dailymail.co.uk/sciencetech/article-2832751/Rosetta-s-probe-stable-Philae-confirms-s-holding-67P-scientists-fear-tumbled-side.html
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oh well, it was fun while it lasted
longship
(40,416 posts)The ESA Blog states very clearly that Philae rotated with respect to the z-axis, which is a vertical rotation.
The Daily Mail sucks for writing that Philae is on its side.
Baclava
(12,047 posts)While it was touching down, the lander bounced twice -- almost as if the comet were a trampoline. The first bounce was major. It lasted almost two hours and took the lander about two-thirds of a mile above the comet's surface.
The second bounce was smaller and lasted just a few minutes, said Stephan Ulamec, the Philae landing manager. The craft's harpoons failed to attach it to the surface after touchdown Wednesday but it's now stable, scientists said.
"We know how we landed, but we don't know where," said Stephan Ulamec, Philae lander manager at the DLR German Aerospace Center. "We landed three times."
The lander then settled in a shadowy part of the comet near a cliff, where it is only getting 1 1/2 hours of sunlight a day. At its planned landing site, Philae would have gotten six or seven hours of sunlight.
The difference is crucial because Philae will need to rely on solar power after its batteries run out after about 60 hours, and this will affect how much work the probe can do on the surface, mission officials said.
Scientists also said Philae landed with two legs on the ground and one foot in the air during its final touchdown. Ulamec said the lander has the capability to make a little "hop" on the surface, which could help it get into a better position, but the maneuver would be risky and it is not likely ESA will try it.
And because Philae's harpoons failed to keep it tethered to the comet, ESA officials are also wary of drilling into the comet as planned. Their concern is that the force of the drills on such a low-gravity body could cause the lander to move again.
http://www.latimes.com/science/sciencenow/la-sci-sn-philae-update-20141113-story.html
longship
(40,416 posts)The ESA Blog says nothing about it being on its side.
Baclava
(12,047 posts)but hey - it stuck the landing, that's what this was all about
the engineers got it to land, the science is extra
longship
(40,416 posts)It's just too bad the thrusters and the harpoons did not function.
One is tempted to wonder if the first bounce was possibly caused by the harpoon firing. Probably not. But hey.
ChisolmTrailDem
(9,463 posts)one of the most amazing achievements ever accomplished by mankind.
To me, if Philae fell over the side of the comet today, it would still be a raging success.
randome
(34,845 posts)Jesus, do I have to do everything around here?
[hr][font color="blue"][center]A 90% chance of rain means the same as a 10% chance:
It might rain and it might not.[/center][/font][hr]
Baclava
(12,047 posts)Solar Orbiter, the spacecraft has a target launch date of 2017. The launch vehicle of choice has not been named, although it was stated that NASA will contribute one full instrument, one sensor and the launch vehicle
To get a close-up view of the Sun and to observe the solar wind before it becomes disrupted, Solar Orbiter will fly to within 45 million kilometres of the Sun, closer than Mercury. It will image the poles for the first time, helping ESA to understand how the Sun generates its magnetic field.
Solar Orbiter is a fantastic mission, added Prof. Cañete. It will help us understand how the Sun, essential to almost all life on Earth, forms the heliosphere and the origin of space weather, which can have an enormous influence on our modern civilization
http://www.nasaspaceflight.com/2012/04/esa-sign-big-money-deal-astrium-uk-solar-orbiter/
randome
(34,845 posts)It's amazing we can do things like this.
[hr][font color="blue"][center]Aspire to inspire.[/center][/font][hr]
muriel_volestrangler
(101,355 posts)In that time, it is now thought that Philae reached a altitude of about 1km and drifted about 1km away from the original site. On a comet of just 4km in length, that is quite significant.
The second jump was just for a few minutes and resulted in the lander coming to rest somewhere in the original landing site candidate known as site B.
http://www.theguardian.com/science/across-the-universe/live/2014/nov/13/rosetta-mission-philae-lander-live-coverage-comet-esa#block-5464ce3be4b0e5251178e8c5
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A new panoramic image will be taken after the MUPUS deployment to see if there has been any movement.
In parallel, there is a big effort from the Rosetta orbiter team to try to pinpoint Philaes position. This will be done with images from the Osiris camera and with the CONSERT radar instrument.
CONSERT communicates with Philae. It is designed to be beam radar through the interior of the comet to reveal its internal structure. When Rosetta is directly overhead, CONSERT can provide highly accurate triangulation.
http://www.theguardian.com/science/across-the-universe/live/2014/nov/13/rosetta-mission-philae-lander-live-coverage-comet-esa#block-5464dd0ae4b0867bcfaf6458
http://www.open.ac.uk/science/research/rosetta/mission/philae-lander/mupus
Baclava
(12,047 posts)You know the lander is talking to u...
https://twitter.com/ESA_Rosetta
ESA Rosetta Mission @ESA_Rosetta .@Philae2-incredible panoramic postcard from the surface of #67P
ChisolmTrailDem
(9,463 posts)exactly what I had imagined when I made this comment: http://www.democraticunderground.com/10025810591#post8
The little critter is literally standing (laying?) on the edge of a cliff, about to fall off.
I predict this craft will not remain there as the comet approaches the sun.
I am watching the latest from ESA recorded earlier today for the latest on the situation with Philae here: http://www.esa.int/Our_Activities/Space_Science/Rosetta/Rosetta_media_briefing_replay rather than depending on lay and stupid, and non-science-believing rightwingnut-leaning media sources and nooz/snooze dispensaries for their perspective.
muriel_volestrangler
(101,355 posts)What happens from here? They're doing as much science as they can without making any mechanical motions. That means no MUPUS surface properties experiments, or use of the APXS, and no deliveries to the gas chromatograph mass spectrometers. There is discussion of possibly using some of these moving devices to attempt to pop the lander up off the comet again, to try to get it into a position where they could recharge the battery. But if they do that, it will be a last-ditch effort.
http://www.planetary.org/blogs/emily-lakdawalla/2014/11131025-philae-status-a-day-later.html
Baclava
(12,047 posts)The orbiter Rosetta will accompany the comet through perihelion (August 2015) until the nominal end of the mission.
muriel_volestrangler
(101,355 posts)muriel_volestrangler
(101,355 posts)Esa is considering whether to spin Philaes flywheel to bounce the lander into a new position where its solar arrays will get more sunlight to recharge its batteries.
80-90% of the intended science will have been carried out, but theres some doubt over whether all the data will be uploaded before the lander loses all power.
All the landers instruments are working well. MUPUS and APXS instruments were used last night and the drill was activated. They will know this evening whether drill samples have been taken successfully. There will be more radar data to try to locate Philae.
http://www.theguardian.com/science/across-the-universe/live/2014/nov/14/rosetta-mission-philaes-third-day-on-comet-as-it-happens#block-54661ab8e4b0867bcfaf65ce
They also say that, as the comet gets closer to the sun, there's a possibility that the solar power will become enough to wake Philae up again.
muriel_volestrangler
(101,355 posts)...
The second image is 1 min 26 seconds after first touchdown. The touchdown is seen as a dark area. This dark area could be considered as strong indication that the lander touched down at this spot (possibly raising dust from the impact). The third image is the same as the second, but also shows a green square; this is the computed touchdown point.
They were taken from a distance of about 15 km from the surface, giving an approximate scale of 1.3 m per pixel. The dark spot appears to be within less than 10 m of the computed touchdown point.
http://blogs.esa.int/rosetta/2014/11/14/philaes-first-touchdown-seen-by-rosetta/
Not bad, aiming at a rotating target from 22.5km away, 7 hours earlier.
muriel_volestrangler
(101,355 posts)It ends a tense wait for the European Space Agency (Esa), amid fears that the lander's battery was about to die.
Scientists will be most keen to see if the probe has managed to get a surface sample of the comet with its drill.
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The first good news to emerge from the latest radio contact is that Philae appears to have suffered no major disruption from the drilling. And the instrument onboard the probe that was due to receive the first sample, Cosac, is feeding science data to Earth.
http://www.bbc.co.uk/news/science-environment-30058176
Batteries are on the point of running out:
https://twitter.com/Philae2014
https://twitter.com/esaoperations