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Fascinating Rosetta Image Captures Philae's Comet Bounce

mpicpp points out that high-resolution pictures have been released of Philae's landing. "The hunt for Rosetta's lost lander Philae is gaining steam as scientists pore over images from above the comet that may help reveal its final location. The ESA released an image Monday taken by Rosetta's OSIRIS camera showing Philae's first bounce on the comet. The mosaic includes a series of pictures tracking the lander descending toward the comet, the initial touchdown point and then an image of the lander moving east. 'The imaging team is confident that combining the CONSERT ranging data with OSIRIS and navcam images from the orbiter and images from near the surface and on it from Philae's ROLIS and CIVA cameras will soon reveal the lander's whereabouts,' says the ESA."

38 of 69 comments (clear)

  1. The Who? by Tablizer · · Score: 1

    Just hire a pinball wizard to figure it all out.

  2. Odds are it's already in a martian chop shop.... by Anonymous Coward · · Score: 2, Funny

    Never put 20 inch rims on your lander.

  3. Can Rosetta power Philae? by DigitAl56K · · Score: 2, Interesting

    I haven't really been following this too closely so this may be entirely impossible, but if Philae is located, could Rosetta be positioned to reflect enough sunlight onto Philae to help power it?

    1. Re:Can Rosetta power Philae? by Anonymous Coward · · Score: 1

      Even if Rosetta could be used as a mirror, which I doubt, it is probably far too small to do that efficiently.
      Also, assuming that you could move Rosetta very close to the comet to reflect enough light then it would be subject to its gravity.
      This is a small force but Rosetta would not be able to stay perfectly stationnary so the effect would not last for very long.

    2. Re:Can Rosetta power Philae? by Anonymous Coward · · Score: 4, Insightful

      That would consume a lot of fuel on Rosetta to keep it constantly pointed, and even then it would only illuminate the probe for a part of the day. The orbiter has priority in the mission (a lot of things were cut from the lander design to make the orbiter better, as it has more instruments central to the main goals), so that would be sacrificing the high priority component for the lower priority component, assuming it would work (the amount of reflection you would get off solar panels would either be weak, or involve using angles that would mean Rosetta gets almost no power).

    3. Re:Can Rosetta power Philae? by ColdWetDog · · Score: 1

      I think you'd be better off sending Bruce Willis and a drill. Pull one of the Shuttles out of retirement, get J.J. Abrams to direct the thing and there is a chance that it would work out.

      --
      Faster! Faster! Faster would be better!
    4. Re:Can Rosetta power Philae? by cytg.net · · Score: 1

      So a geostationary orbit over philae is out of the question? It wouldnt take an enourmous amount of material and a little optics to focus some photonics down on our little lander. I wouldnt be surprised if such mechanics was proposed back in the planning stages.

    5. Re:Can Rosetta power Philae? by cytg.net · · Score: 1

      I think that planning a mission like this is about backup, redundancy, contingency upon contingency eliminating single points of failures as much as possible, and I am sure the scenario where harpoons AND the cold gas thruster both failed were not worth a tertiary backup plan. Thats what I think. But hey I bet they didnt think of "better harpoons" .. you should write them with your thoughts on the subject.

    6. Re:Can Rosetta power Philae? by Anonymous Coward · · Score: 2, Informative

      They had backups, but those also failed. Also, no part of the lander could be considered a single point of failure in the big picture since the orbiter had the more important gear. They revised the design at one point on the recommendation that the orbiter was better suited for getting some of the composition and mapping data that was the main goal of the project, so the lander was scaled back. Adding more mass to the orbiter at the expense of other stuff it was carrying to support the lander would be still sacrificing higher priority stuff for lower priority stuff. Especially considering that the majority of instruments on the lander were of limited use, and only three of the ten instruments would be of much (but diminishing) use after a couple days with continual power. Short of a complete redesign of the mission, there is not much reason to cut corners elsewhere or increase the cost to extend the life of the lander.

      A stationary orbit would not be straightforward, as for the mass and rotation speed of 67P, you would need a distance of ~3 km from the center of the comet, which is close enough your orbit won't be a simple conic section. You still have to keep Rosetta pointed at the lander, which is the fuel consuming part mentioned above, and probably need some more spinning to get reasonable amount of power to the orbiter, not to mention now the orbiter will have more time in the shade too.

    7. Re:Can Rosetta power Philae? by Thanshin · · Score: 2

      Asked and answered (although I'd need hours to find the tweet with the answer by the ESA to this exact question)

      The answer was:
      "No, because solar panels are done to absorb light, not reflect it."

  4. Imagine when Philae is re-discovered by Anonymous Coward · · Score: 1

    Imagine millions of years from now if some civilization come upon this asteroid, and their awe and astonishment when they find this forgotten, dusty satellite, resting in the shadows beneath a crevice.

  5. "...moving east." by Payden+K.+Pringle · · Score: 1

    East. Now in space.

    1. Re:"...moving east." by jfengel · · Score: 2

      Well, yeah. The comet rotates. The direction of its rotation is east. It's as good a coordinate system as any.

    2. Re:"...moving east." by Carewolf · · Score: 2

      East. Now in space.

      It has always been in space, it is the rotational direction where the sun rises.

    3. Re:"...moving east." by Payden+K.+Pringle · · Score: 1

      I'm just going to hazard a guess and say that the cardinal directions have to do with the magnetic field of the body itself. At least, that's what I always thought growing up.

      i.e. If we were to go to Mars, we'd define the poles as North and South (not sure if there are specific characteristics or if we just pick randomly), then define East/West based on that.

      This comet probably doesn't have a magnetic field though.

    4. Re:"...moving east." by An+dochasac · · Score: 1

      ... except on Discworld where:

      "Cardinal directions within the Discworld are not given as North, South, East and West, but rather as directions relating to the disc itself: Hubward (towards the centre), Rimward (away from the centre) and to a lesser extent, turnwise (direction of the disc's rotation) and widdershins."

    5. Re:"...moving east." by TechyImmigrant · · Score: 1

      East. Now in space.

      It has always been in space, it is the rotational direction where the sun rises.

      I thought the sun stayed more or less in the same place.

      --
      I should use this sig to advertise my book ISBN-13 : 978-1501515132.
    6. Re:"...moving east." by Trogre · · Score: 1

      What if it is spinning on more than one axis, ie tumbling? The direction where the sun rises for a given point on the comet will change all the time.

      I have no idea if the comet is actually doing this, but I imagine that being a scenario where computing "east" being rather difficult.

      --
      "Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
    7. Re:"...moving east." by hcs_$reboot · · Score: 1

      It has always been in space, it is the rotational direction where the sun rises.

      Don't think though. East is basically Right on the pictures, based on Rosetta (camera) direction.

      --
      Slashdot, fix the reply notifications... You won't get away with it...
    8. Re:"...moving east." by Carewolf · · Score: 1

      What if it is spinning on more than one axis, ie tumbling? The direction where the sun rises for a given point on the comet will change all the time.

      I have no idea if the comet is actually doing this, but I imagine that being a scenario where computing "east" being rather difficult.

      A ball at least can only rotate around one axis (any superposition of two rotations can be described as a single combined rotation), but the poster above me had the better answer. East is the direction of the rotation, it just happens to also be where everything stationary or far away that is not constantly visible would rise.

    9. Re:"...moving east." by tinkerton · · Score: 1

      I checked that for one of the previous posts: http://blogs.esa.int/rosetta/2... lists the declination and ascension of its axis of rotation so the wobble must be modest.

      And here's asteroid Toutasis. It wobbles. http://www.solarviews.com/raw/...

    10. Re:"...moving east." by TechyImmigrant · · Score: 1

      It was? Oh well, I blew it.

      --
      I should use this sig to advertise my book ISBN-13 : 978-1501515132.
  6. Re:Fucking disaster by Anonymous Coward · · Score: 1

    You forget the most important thing that occurred, which is the shirt the scientist was wearing when interviewed on TV. Why that shirt was not in proper style. The horror!

  7. Look for a loud shirt? by Anonymous Coward · · Score: 1, Funny

    And listen for the shouts of the perpetually outraged?

  8. Re:Fucking disaster by Tablizer · · Score: 5, Informative

    They're trying to dress it up and say it was a success, but you just can't put lipstick on a pig.

    Hey, they've done something that nobody has done before. Kudos are in order. Low-gravity landings on giant loose lint-balls are still new territory.

    The amount of science returned is still unknown because they are still sifting the data. At the very least, they got close-up photos of the surface of a comet for geologists to study.

    I hope they take their lessons and make a better comet mission.

    Remember, the US Ranger program took 7 tries before they had success. The comet mission had partial success on the first try! Practice makes perfect.

    Perhaps they can make the next one spherical and not require any particular landing orientation. Put wire-frame bumpers on it and let it go ahead and bounce. It can adjust its angle after a landing.

  9. not disaster by globaljustin · · Score: 1, Insightful

    aw, c'mon now!

    everyone in the known universe wanted to see those harpoons...they didn't launch...that's a failure...

    same with the retro-booster

    but it is nonsense to call it a disaster

    a 'disaster' is a shuttle exploding, or a probe failing because of metric/english unit conversion errors (google it)...

    for this mission...if Rosetta had missed it entirely, no rendevous...or if the lander had totally not worked...maybe that's a 'disaster'

    but this is not that

    --
    Thank you Dave Raggett
  10. Re:Fucking disaster by mythosaz · · Score: 1

    ...but feminism. :(

  11. Re:Fucking disaster by Anonymous Coward · · Score: 1

    You Americans and your petty envy.

  12. Re:Fucking disaster by LinuxIsGarbage · · Score: 4, Insightful

    The purpose of the mission wasn't just to land something on the surface and have it continuously live stream.

    They still have the orbiter with a big instrument suite, which will continue to provide useful data.

    The lander had two goals. One was to operate all the instruments and collect data at least once. The non-rechargable 1200Wh Li/SOCl2 batteries allowed this to happen, exactly as planned, even without the sun. It didn't land where planned, but it did land, collect the data, and transmit it.

    The second part was a longer term monitoring, which the solar cells recharge the smaller 150Wh Li-Ion batteries to support. This is the part that's in jeopardy.

    Remember Voyager 1, the probe sent out in 1977 that's 18 light hours away? The Plasma Spectrometer and Photopolarimeter System sensors were defective. Four others sensors had to be disabled because it's running out of power. What a colossal boondoggle.

  13. Re:Fucking disaster by Anonymous Coward · · Score: 5, Insightful

    Put something in orbit. CHECK
    Land on a comet. CHECK
    Perform sciency stuff: CHECK

    The landing wasn't perfect. All the sciency stuff was complete at a little over 80% accomplished.

    Measure this in scientific progress, not scientific perfection. If you are looking for perfection on the first attempt of anything, get out of science.

  14. Re:Fucking disaster by pseudofrog · · Score: 5, Insightful

    A summary, for those who were fortunate enough to miss this:

    1. Dude wears a shirt with scantily-clad women. Some people say it's kinda sexist.
    2. Dude sincerely apologizes. Those who complained accept.
    3. Everyone moves on. Lessons learned. Yay! Pretty comet pictures!
    4. LOL just kidding. A bunch of "supporters" who won't STFU see this is a great opportunity to attack straw feminists and comment on every single article mentioning the mission. Those who objected to his shirt, typically women scientists/engineers, are slandered as "taking away from his accomplishments" despite writing about this mission for, in some cases, years. Assholes start an Indiegogo campaign to buy him, specifically, a watch for being "bullied," which is forcing him to deal with a situation he's clearly ready to move on from. MRA and GamerGate types congregate, attacking and doxxing anyone who had the slightest of problems with his shirt.

    So of course we have folks on /. pretending that a handful of articles about a shitty T-shirt and a subsequent "forced" apology show that lolfeminists, even those with PhDs in relevant, don't care about this mission.

  15. Re:Fucking disaster by Trogre · · Score: 1

    Some equipment didn't work, but the mission objective was still accomplished. The science data they set out to collect was still obtained. I call that a success.

    By your logic, Apollo 11 was not a success because Armstrong had to resort to manual control when landing.

    --
    "Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
  16. Re:Fucking disaster by TropicalCoder · · Score: 2

    "The science data they set out to collect was still obtained." Do we really know yet if the probes and drills actually reached down below the surface? It appeared that lander was sticking up and I have my doubts. I think it would be wonderful if they actually got the samples they hoped they would get, but I am not convinced. There is an article behind a pay wall in the WSJ that says an instrument discovered an organic compound that was first detected in the comet’s atmosphere. Says the molecule was detected by an instrument on the lander "sniffing" the comet's atmosphere. Seems there is no more information than that. Hard to say if we can take that to mean they actually got their samples. Sniffing the comet's atmosphere != soil samples.

  17. Re:Moving "east"? by dotancohen · · Score: 1

    Where is "east" on the comet?

    The comet's axis which appears to spin in a counterclockwise direction from above is its north pole. From a location in which the pole is perpendicular to the angle of view, east is the direction against the comet's rotation, i.e. the direction which appears to be rotating towards you.

    Admittedly, this is somewhat difficult to imagine for a non-spherical object, but it works out.

    --
    It is dangerous to be right when the government is wrong.
  18. Re:Fucking disaster by Mathinker · · Score: 1

    > But when you're paid to represent someone else

    Obviously, then, whoever hired this guy failed utterly. Just kidding. I find it much more likely that whoever hired him, didn't hire him based on the "15 minutes" of public representation he'd end up making at the end of the mission.

    And therefore, whoever decided, not that long ago, that he should be the one to be a public representative, failed. It was probably some PHB who doesn't know any of the technical staff well enough to know that this guy needed to be carefully managed in this particular regard.

    > and not an attention-seeking douchenozzle

    Do you know him personally? Because my guess is that he's probably one of those technically adept, socially inadept people we often meet in our line of work. Especially since I saw a headline that he broke down and cried when he apologized? You'd think that "an attention-seeking douchenozzle" would have just used the apology for... more exposure. Of course, it could have been an act, I guess.

  19. Re:Fucking disaster by stevelinton · · Score: 2

    Really?

    Hard to know where to start. Firstly the whole landing was just a small part of the mission. The orbiter is still up there and, all being well, will follow the comet in to
    perihelion, observing all the way.

    Secondly, think about the trade-offs of planning a space probe. You can make things more robust and more redundant, design more conservatively, etc. reducing the risk of things failing, but that costs you mass and power (and possibly money) which are rigidly limited. So you would have to take fewer instruments. The design optimises the expected science return by taking some risks.

    The lander was intrinsically high risk, because no one had any idea what the surface of a comet is like. They had to gave it a bunch of different ways of hanging on designed around some plausible guesses. The lander has no propulsion at all (those mass trade-offs again), so it has to put up with wherever it hits. They knew solar power on the surface was uncertain, so they had enough juice in the non-rechargable battery to do the highest priority science.

    In the event, two systems failed -- the cold gas hold down thruster and the harpoons. No one knows why yet, but building systems on a very tight mass budget that can work after 10 years in space is not easy. In addition, the surface of the comet seems to be harder than anyone really expected.

    Given the challenges, getting any science at all back from the lander is amazing and a bonus to the main mission which is the orbiter.

  20. Re:East? by Tablizer · · Score: 1

    What is east on a comet?

    That's easy, opposite of west.

  21. Re:Fucking disaster by Tablizer · · Score: 2

    In different words, you agree then that this comet landing was not actually a success.

    I don't see how that follows from the quoted text.

    Regarding the harpoon, many "successful" US missions also had problem spots. For example, Galileo's main antenna didn't open, greatly limiting imaging data, but still did lots of other measurements. And its atmosphere probe had a key part on backward, but got lucky and still managed to work. Voyager's antenna boom kept shifting around, missing some key shots. Pioneer 10 and 11 got confused by Jupiter's radiation and missed a couple of moon photos. Viking 2's seismometer didn't work. Apollo 11's guidance computer got swamped with processing jobs and stopped working. Spirit's memory got full, stopping all work for a couple of weeks.

    There is no AAA out there: you improvise and cross your fingers.