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20

Philae can last many years (it's meant to survive perihelion pass, it has solar batteries, and it can withstand the long deep-space hibernation (it did it once already). Theoretically it could last as long as Opportunity on Mars. Unfortunately it doesn't have antennas to reach Earth - only Rosetta. It depends on Rosetta to forward data back to Earth. As ...


19

The Wikipedia page for Philae suggest a 1-6 week mission duration. However, the design goal is always conservative. Consider the Mars rovers (Spirit and Opportunity) whose mission design goal was 92 days and Opportunity is at 3945 days now and going strong. They design longer, but ensure the minimum. So how long could it last? No one specifically knows,...


17

The Philae lander's last observed location in September 2016 is on the comets smaller lobe, settling there after a few bounces following a 2 hour "flight". It is reasonable to assume that it is still there or nearby, but 67P is a comet, and even though it does not get closer than 1.24 AU from the Sun, there is always a possibility that it might have moved ...


16

According to this statement by the ESA, Rosetta is presently sending signals to the ground stations at about 28 Kbps; Ignacio says that the spacecraft's own telemetry downlink uses about 1 or 2 Kbps of this, so the rest is being used to download science data from Rosetta and lander science and telemetry from the surface. Given that you have 28 kbit/s for ...


16

The harpoons are intended to hold the lander to the surface long enough to get the ice screws on the lander's legs in securely. The ice screws are intended as the more permanent hold-down solution. Bear in mind that the comet offers essentially no gravity; imagine trying to drive a wood screw into the ceiling without pushing the screwdriver upward at all. ...


14

Let me just expand a bit on @Tildalwave's answer. Most landers on airless bodies need a propulsion system, because they will be going too fast otherwise to land. But that's only because most landings have been done on objects with a lot of gravitational mass. Let's just try and figure out what the escape velocity would be. Wikipedia gives us the following ...


13

It did not travel in a straight line. It passed 4 planets for gravity assist1 in order to gain the velocity and change to the trajectory2 required to meet the comet. See Gravity Assist: Rosetta – Rosetta – first spacecraft to match orbit with a comet for details. The comet is currently approaching the Sun, but further from the Sun than Earth. So ...


9

Yes No (see update). From ESA's 15 November 2014 update on the Rosetta mission: Pioneering Philae completes main mission before hibernation 15 November 2014 Rosetta’s lander has completed its primary science mission after nearly 57 hours on Comet 67P/Churyumov–Gerasimenko. After being out of communication visibility with the lander since ...


9

Remember that Philae was designed in the 1990's. MorphHex is at the edge of what technology of today can accomplish, it wasn't possible 20 years ago when Philae was designed. Most of all because adaptability would have to be done autonomously because of the 28 minutes time delay. The harpoons were supposed to fire once two legs had hit the ground. But it ...


8

While nothing is certain, even if there are no equipment failures it's unlikely that Philae would survive the comet becoming highly active as it approaches perihelion in fall 2015. EDIT: Seems I was wrong. Quote from Dr Ulamec, lander team manager: "Risk of the lander being blown off the surface by strong cometary jets is low - it has too high a density"


8

Actually, Philae does have a propulsion system. As explained in this related question, its Active Descent System uses a cold-gas thruster to propel the lander towards the comet if needed.


8

Rosetta's approach and odd orbit (described well in the question and answer here: Is this really Rosetta's orbit around 67P?) are designed to gather the necessary information needed to achieve a safe orbit and eventually land Philae. The landing site is being selected now: "As many as five possible landing sites will be identified by late August, before ...


8

Yes, the science/engineering teams will be able to use the radio communications between Rosetta and Philae to better pinpoint the location of the lander. However, by far the best data for finding the lander will be the CONSERT instrument, which has a part on the lander and a part on the orbiter. CONSERT works by transmitting radio signals from the orbiter to ...


7

Below is pair of a high resolution images from the OSIRIS camera of where Philae's first touched down, overlaid upon one another. One was pre-touchdown and the other very shortly after touchdown (and bounce): Image source: http://www.esa.int/spaceinimages/Images/2014/11/Philae_spotted_by_Rosetta_after_first_landing The Rosetta operators knew to look at ...


7

It turns out that scientists thought the same thing very recently. According to this Anatomy of a Comet article at NASA Jet Propulsion Laboratory's website, related to the Rosetta mission, "Scientists used to think that it was solid and firm, but NASA’s Deep Impact mission (2005), in which Rosetta participated, surprised them. They found that the ...


6

It doesn't really need it and it would needlessly add to its mass. Rosetta will assume a relatively slow and probably highly elliptical orbit around 67P/Churyumov-Gera...aaagh! Chury!, with the perigee at only roughly a kilometer away from it. The orbit has not yet been determined though, see my related question and the answer there. It likely won't be until ...


6

Technically yes, definitely. It might have even been as Rosetta and Philae were designed, but was not considered a priority or was thought wasteful to already limited resources. For example, from technical standpoint, we frequently get downstream in the order of several megabits per second (Mb/s) from Mars orbiters (check for example the DSN Now tool, select ...


5

The next comet lander will definitely be better designed. Before the Rosetta mission, our knowledge about comets was very limited. When Philae was designed, the engineering team had no idea what they would encounter. No probe ever got closer to the nucleus of a comet than a few 100 km (The Deep Impact craft crashed its impactor into comet Temple-1 after the ...


5

In addition to what has been stated in other answers, it seems "if everything goes according to plan" is quite a bold assumption as there is serious concern that the lander may be stuck in the shade and/or wedged in a hole. In that case, battery life is about 60 hours before the lander must rely on solar power. This means that with bad luck, it might all be ...


5

There are two specific things that we have to have to get pictures in this case: Communication: PearsonArtPhoto already talked about this. If we can't receive information from the probe we can't get pictures. The instruments cannot have been damaged: Take a look at this picture of Philae: (Note: instruments are described on the Wikipedia page) The ...


5

Ptolemy instrument sniffed water and 'organic' molecules before hibernation. (source: ESA) From Wikipedia: An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. Exact composition of Ptolemy detected organic molecules has not yet been announced, and according to some recent ...


5

According to this SETI Talk 2014 Dec 16 by Jens Biele at German DLR, the "grabbing mechanisms" failed in several ways. The cold gas thruster that should've pushed it down gave an error indication even before landing. But since there was nothing they could do about it they landed as planned anyway. They had wired the harpoons wrong so they did not fire on ...


5

The surest currently known way to detect DNA and analyze it to rule out sample contamination with genetic material from the Earth hinges on rapidly multiplying the DNA molecules via PCR (polymerase chain reaction). No PCR kits have been deployed to space so far. However, this is going to change: Boeing is considering sending Amplyus' miniPCR platform to the ...


4

Minerva was fired towards the asteroid by Hayabusa, but it did not have its own propulsion system. The problem was that Minerva was released at the wrong moment: While awaiting the ground command to deploy MINERVA, the Hayabusa mothership was under autopilot control to maintain a set distance above the surface. As it drifted up or down to a range limit, ...


4

Philae is most certainly designed to land on an unknown surface. It is not designed to be mobile on such surfaces, like the robots in the OP's video are. Note that Philae has three legs and an extremely low center of gravity. It's tipping angle is probably above 45 degrees, and certainly far above 30 degrees. Three legs is the most stable and self-adapting ...


4

This is indeed possible. The US spent a fair amount of money in the 60s and 70s on beamed power. In recent years it has gotten some more interest for lunar rovers that can survive the 14 day lunar night (without RTGs). The losses are not negligible, and the pointing requirements are rather extreme but in practice there's no reason why this couldn't happen. ...


4

As of June 11th, it is still unknown according to this ESA blog post: Rosetta and Philae teams continue to search for the current location of the lander, piecing together clues from its unexpected flight over the surface of Comet 67P/Churyumov-Gerasimenko after its initial landing on 12 November. However, I understand that it is looking likelier that ...


3

Nothing will happen with the Philae lander now for some undetermined time. How much time is not exactly clear though, but ESA operations said not to expect the lander to wake up in a couple of days or so. From Rosetta blog: From now on, no contact would be possible unless sufficient sunlight falls on the solar panels to generate enough power to wake it ...


3

Based on the fact that we don't know 100% the status of Philae right now, but we do have some descent photos, I'd say yes, it is possible, so long as contact can be maintained.


3

The odds of any unexpected event altering Philae's trajectory is negligible. I suspect that the most likely cause for putting it off-target, ironically, would be a propulsion system malfunction, or a leak in a propellant tank! Not sure what you mean with the last question, "Is it's mass of 100kg on Earth, and Chury's infinitesimal gravity adequate to ...


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