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Space

Philae's Batteries Have Drained; Comet Lander Sleeps 337

Posted by timothy from the amazing-feats-done-dirt-dirt-cheap dept.
astroengine (1577233) writes "In the final hours, Philae's science team hurried to squeeze as much science out of the small lander as possible. But the deep sleep was inevitable, Rosetta's lander has slipped into hibernation after running its batteries dry. This may be the end of Philae's short and trailblazing mission on the surface of Comet 67P, but a huge amount of data — including data from a drilling operation that, apparently, was carried out despite concerns that Philae wasn't positioned correctly — was streamed to Rosetta mission control. "Prior to falling silent, the lander was able to transmit all science data gathered during the First Science Sequence," said Stephan Ulamec, Philae Lander Manager. "This machine performed magnificently under tough conditions, and we can be fully proud of the incredible scientific success Philae has delivered.""
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Philae's Batteries Have Drained; Comet Lander Sleeps More

Philae's Batteries Have Drained; Comet Lander Sleeps

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  • Hey don't worry (Score:2, Funny)

    by Anonymous Coward

    3D printing and private space means that we'll soon have dozens, no, hundreds of private space probes out there searching for mineable asteroids and comets because there's just so much money to be made out there!

    • Don't know why this has been modded funny, it just depends on the interpretation of "soon." Give it another hundred years and the solar system will indeed be crawling with private robots, unless we somehow manage to seriously fuck up our civilization until then. On a cosmic time scale another hundred or two hundred years is nothing.

      What annoys me a bit, though, is that I'm probably born too early to be able to download my consciousness into a machine during my lifetime, so I won't see what the future brings

      • Re: (Score:2)

        by itzly ( 3699663 )

        Give it another hundred years and the solar system will indeed be crawling with private robots

        Private robots suggest there's profit to be made, which is rather far fetched.

  • ShirtStorm (Score:5, Insightful)

    by Anonymous Coward on Friday November 14, 2014 @11:30PM (#48390025)

    I think we're all more interested in the shirt drama than any of this science stuff!

  • We may hear from Philae later (Score:5, Interesting)

    by AbrasiveCat ( 999190 ) on Friday November 14, 2014 @11:38PM (#48390041)
    While the main battery is nearly depleted and at this point there is not enough solar power striking the solar panels to boot it back up, as the comet approaches the sun the light intensity should go up. We can hope that the existing conditions provide enough power to prevent damage to the landers electronics. Then as the comet approaches the sun and the comet either changes origination to provide more light or just Philae get more intense light it may rise again. That would be grand!

    • Re:We may hear from Philae later (Score:5, Interesting)

      by Zordak ( 123132 ) on Friday November 14, 2014 @11:46PM (#48390061) Homepage Journal
      Of course, the comet will also start shooting off monster steam blasts, which could easily blast Philae off at escape velocity. The next Twitter update from Philae could be "I'm Lost in Space!"

      • Of course, the comet will also start shooting off monster steam blasts

        Only if comets are balls of ice, like we used to think. Shooting off monster blasts of vaporized rock needs a lot more heat, so there's probably a chance to charge up the batteries before then :)

      • heck, just the comet shaking BEFORE it starts out-gassing might send Philae off. A human there could easily punt Philae off the surface way over escape velocity. Luckily Rosetta will see that happening pretty quickly; but your probably right it will get shaken off before it can recharge much. Maybe if it can recharge a bit first they can actually fire the harpoons. ARG, A HUMP LIKE A SNOWHILL! IT'S COMET 67P!

        • Re: (Score:2)

          by Dunbal ( 464142 ) *
          I wonder if you could kick it back into Earth orbit. That would be cool.
          • Philae has the same orbital parameters as the comet. it would take quite a lot of delta-v to convert that orbit to orbitting the Earth. After all, it took ten years and four planetary slingshots in order to get it there in the first place.

      • Especially when escape velocity on a comet is a white guy's jump.

    • Fair-weather power sources are lame... (Score:4, Insightful)

      by KonoWatakushi ( 910213 ) on Saturday November 15, 2014 @02:20AM (#48390343)

      After all the trouble and expense of sending a probe or lander out into the unknown, it seems a waste not to provide them with an RTG [wikipedia.org] for reliable power. Solar panels have hobbled Mars rovers as well as other spacecraft.

      • Re:Fair-weather power sources are lame... (Score:4, Insightful)

        by itzly ( 3699663 ) on Saturday November 15, 2014 @02:59AM (#48390417)
        Given a fixed budget, what part of the mission would you have taken out to replace with an RTG ?
        • Um, probably would have left off the solar panels and all that charging equipment. Pioneer 10 ran for 30 years off a single kilo. A few grams would have kept this lander probe going for quite some time.

          • Re:Fair-weather power sources are lame... (Score:4, Informative)

            by itzly ( 3699663 ) on Saturday November 15, 2014 @05:56AM (#48390793)

            Pioneer 10 used four SNAP-19 radioisotope thermoelectric generators (RTGs). They were positioned on two three-rod trusses, each 3 meters (9.8 ft) in length and 120 degrees apart. This was expected to be a safe distance from the sensitive scientific experiments carried on board. Each of the SNAP-19 generators was 35 pounds, not including the supporting trusses.

            So, it seems you're overlooking some aspects of this issue. Namely the weight of the total generator, not just the plutonium. Also, there may be a requirement to mount the RTGs on a truss to keep them away, which would greatly complicate the design of the lander. And of course, apart from the design, mass there's also the simple cost issue. Solar panels are probably cheaper to obtain and install than plutonium based RTGs

      • Re:Fair-weather power sources are lame... (Score:5, Insightful)

        by Yoda222 ( 943886 ) on Saturday November 15, 2014 @04:23AM (#48390599)
        You cannot really blame ESA to not take into account Mars rovers solar panel problems. I think it's very difficult to take problems which happens after the launch of a spaceprobe during the design of this probe. Maybe ESA should hire some fortune teller?

      • Re:Fair-weather power sources are lame... (Score:5, Interesting)

        by l0n3s0m3phr34k ( 2613107 ) on Saturday November 15, 2014 @04:39AM (#48390629)
        Unfortunately we're pretty much out of Pu238. The US just started in 2013 to make it again, but only at 1.5Kg a year. Curiosity used around 4kg of it, so it would take at least 2-4 years to make enough for a single probe. We used to buy decommissioned nukes from Russia and reprocess it, but now a) Putin hates us and b) they too are pretty much out of decommissioned nuclear material to even sell. Maybe by 2017 the USA might have enough to make a single RTG for a deep space mission.

      • Re: (Score:3)

        by tomhath ( 637240 )
        For the weight of an RTG they could have dropped several different probes onto the comet, all of which could have very large solar panels. The lander they have was as much weight as they could deliver; the only thing that failed was the mechanism to attach it.

      • I don't think ESA would ever be cleared to handle plutonium, let alone launch it into space. For starters, I don't know who would have the authority to clear ESA to use plutonium.

      • As has been pointed out earlier, RTGs are bigger than you think. The real moral of the Philae story is that robots, especially those operating outside the latency boundary of teleoperator technology, are pathetically unable to adapt to local surprises. It would have been trivially easy for a human traveling with Rosetta to go EVA and position Philae in a sunnier place, or to right it if it had landed upside down or fallen into a gully. Building in the life supports to get a human that far from Earth is a Ha

    • Re: (Score:2)

      by Dunbal ( 464142 ) *
      The density of particles around the comet should go up too. You don't get much sunlight in a dust-storm. Not to mention it's not very good for the solar panels. While it's good to be hopeful I personally believe that Philae's mission is over.

  • "Yeah, but fuck science... (Score:5, Insightful)

    by Rinikusu ( 28164 ) on Saturday November 15, 2014 @12:22AM (#48390133)

    Because the scientists wear shirts featuring pin-up girls!"

  • Comment removed (Score:5, Informative)

    by account_deleted ( 4530225 ) on Saturday November 15, 2014 @12:55AM (#48390217)
    Comment removed based on user account deletion

  • Sad (Score:5, Insightful)

    by nmb3000 ( 741169 ) on Saturday November 15, 2014 @01:57AM (#48390303) Journal

    When you stop and think about the fact that the Rosetta project was launched over ten years ago [staticflickr.com] (something I didn't realize until recently), it's hard not to feel sorry for the scientists and others on the project.

    The statements the ESA is putting out have a positive spin on them (for multiple reasons, I'm sure), but at the end of the day this has got to be a pretty hard blow to the people personally invested in the project. After the effort required just to get it launched and a decade of waiting, it must be hard on them. Wish them the best of luck for a second chance when the comet nears the Sun.

    • Re:Sad (Score:5, Insightful)

      by steelfood ( 895457 ) on Saturday November 15, 2014 @03:47AM (#48390535)

      Yes and no. On one hand, it wasn't the perfect landing. On the other hand, they waited 10 years for a successful landing. And it happened. That's gotta count for something.

      Remember that ESA probe to Mars that died when it got there? These guys could've waited 10 years to find out that their probe crashed into the comet, or overshot it, or some other calamity befell the lander rendering it inoperative.

      Instead, they did their science, got their data, and have a chance at doing a bit more in the future. That they couldn't do more is unfortunate, but there's a reason they demarcated certain tasks as primary and put enough juice into the thing to complete all of them.

      The probability of abject failure was much higher than the probability of any success, even if imperfect. The fact that this was a partial success, and I would argue it's mostly a success, is worth something.

    • Re: Sad (Score:4, Interesting)

      by troon ( 724114 ) on Saturday November 15, 2014 @04:20AM (#48390587)
      Hey, it landed, did its science and lasted longer than the Soviet Venera landers on Venus, which were a resounding success â" lens caps asideâ¦

  • For he's a jolly good fellow,
    For he's a jolly good fellow, and so say all of us
    And so say all of us, and so say all of us
    For he's a jolly good fellow, for he's a jolly good
    For he's a jolly good fellow, and so say all of us!

  • Earth will get a ticket for dumping.

  • Deep in space, in quiet space...the lander sleeps tonight...

    Still hugely impressive, and it might still wake up eventually.

  • Reading the pre mission discussions, they already knew that the geography of their target was going to be challenging, so I'm curious why they went with solar power (that requires some pretty consistent orientation data) instead of rtg's for Philae? It was further clear that once the comet started outgassing nobody has any clue how that thing is going is going to spin our tumble, an even better reason for rtgs.

    Anyone know?

    • Re: (Score:2)

      by itzly ( 3699663 )
      Mass, availability of Pu-238, price, complexity of the design, interference from the radiation on the instruments, just to name a few things. Also, given the unknown geography, and the challenges of landing, there was a big risk anyway that it would end up with the drill sticking in empty space, and the camera facing a rock. In that case, an RTG would be a waste of resources.

    • Money and fear. Pu-238 is in pretty short supply and (afaik) is not being "made" because the toxicity and complications of manufacture can't justify the price. It was, iirc, a byproduct of nuclear warhead production and now that we're not actively building up an arsenal to turn the planet into radioactive glass there's none to be had.

      The fear part is, of course, the danger that a fairly hot (if small) sample would be a hazard in the event of a launch failure. Now, in reality I think RTG hot products are p

  • Why does NASA's use of the term "science data" sound so weird to me? I mean, sure, it's data collected for scientific purposes, but the turn of phrase just rubs me the wrong way. Maybe it sounds pretentious.

    • Re: (Score:3)

      by gclef ( 96311 )

      "Science data" as opposed to "telemetry data". It's a bit of a jargon term, but makes sense to me.

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