back to article Rosetta probot drilling denied: Philae has its 'leg in the air'

Tough choices lie ahead for Rosetta's Philae scientists after they discovered that the lander’s bouncing touchdown has pushed it into the shadow of a cliff, making it unlikely that its batteries can recharge. Rosetta's OSIRIS snaps Philae as a dot on its way to Comet 67P Philae on its way to Comet 67P. Credit: ESA/Rosetta/ …

  1. Alister

    After such a complex and magnificently executed journey, it's a great shame that the outcome was not as envisaged.

    Just a side thought though, as the harpoons and thruster didn't fire, and they haven't yet used the drills on the landing pads (as I understand it) shouldn't that mean that they have more battery power left than originally planned for?

    1. mi1400

      LMFAO... this is atleast the 2nd time this has happened to Europeans... same happened to Beagle2 MARS disk like non motile robot. to me its more funny than serious... they always happen to be wrong side of stage saying Tadaaaaa!!!!! but spectators are on the other side .....LMFAO!!! :)

      1. werdsmith Silver badge

        "LMFAO... this is atleast the 2nd time this has happened to Europeans"

        This is the first time this has happened.

        1. Anonymous Coward

          "This is the first time this has happened".

          Obligatory link:

          I doubt the probe had such a meeting on contact though!

      2. Anonymous Coward

        Could have been worse, at least it didn't exploded at launch...

      3. Anonymous Coward
        Anonymous Coward

        "same happened to Beagle2 MARS disk like non motile robot. "

        Beagle was a completely different kettle of fish.

        It was chronically underfunded right up until after the last moment, which meant amongst other things that the airbags used were the same ones which had been used, tested and patched in earth's atmosphere and as such were overweight and full of water vapour.

        They spent 6 weeks being baked in my employer's vacuum chambers and we were still sucking out water when they had to be shipped off for launch integration (there was so much water in the airbags initially that it damaged the vacuum pumps). Ideally they should have spent 3 months or more being dessicated and you NEVER EVER fly test articles (This is what killed Apollo 13 - the oxygen tank which exploded was used and damaged in tests performed in 1964).

        The odds are pretty good that Beagle's airbag simply froze solid and never inflated properly (or ruptured during inflation)

        The money that did show up was too late to get replacement airbags

        Had Beagle been properly funded, it very likely would have worked - and it was so cheap/lightweight it would have been easy to build a dozen of the things and plonk 'em down across Mars. The concept is likely to be revisited in the future.

        As for Philae, the gas thuster is an issue (the nitrogen probably froze) but the most lkely reason the harpoons "didn't work" is that by the time they fired, the lander was already several metres off the ground having bounced. An ion engine for soft(er) landing may have been a good idea but you can't go out and attach one now.

        Given the microgravity environment I think I'd have opted for a net or some other form of wide-firing anchor and possible an unfurling solar panel but it's not my project and all that stuff adds launch mass/complexity, etc. Overengineering isn't usually an option for deepspace probes.

      4. Russ Pitcher

        Pot, meet kettle

        Don't be an idiot - how many comets have you landed on? I would prefer to talk about the amazing achievement and put it alongside the great successes of others, particularly NASA, but if we're resorting to purile one-upmanship then I'm game for that. I could point out that Beagle 2 was a low budget mission, about $100 million in today's money. Perhaps I should list a few other failed Mars missions and their rough budgets in today's money:

        Mariner 3 - ~$300 Million ($55M 1970$) - Failed - Fairing didn't separate

        Mariner 8 - ~$300 Million ($55M 1970$) - Failed - Didn't get into orbit

        Mars Observer - ~$1300 Million ($813M 1993$) - Failed - Lost comms before orbital insertion

        Mars Climate Orbiter - ~$460 Million ($327M 1999$) - Failed - Burned up

        Mars Polar Lander - ~$155 Million (110M 1999$) - Failed - Landing failure

        Deep Space 2 - $47 Million (29M 1999$) - Failed - No data returned

        Why not applaud the successes of the incredibly complex decade-long flight and landing and note the fact that the primary objectives were only 60 hours long and it looks like they'll achieve most of them.

        Whichever way you look at it it's something to celebrate.

      5. Yer Mother You Will

        I was going to be childish and retort to the American, mentioning the two space shuttles that blew up and the many rockets they had lost on or just off the launch-pad; oh and the Mars lander that missed Mars by just under 1 million miles, but I thought better of it. Then I realised that NASA never makes errors. In that case I apologise, realizing those pictures and films of the above were from Hollywood, made for Sci-Fi adventure films. Silly me.

      6. Bleu

        But it is


      7. Bleu


        I am not at all pleased for the people who planned and worked on the project, but have to agree with ROFLMAO about commentards and media people who have enjoyed mocking other failed space flights.

        Turns out to have been an even bigger debacle than at the time the article was posted.


        Hell, I even get voted down for pointing out that the ESA is not an organ of the EU!?!

        As of now, I am your only posivote. I am surprised there are no others.

  2. Crazy Operations Guy

    Wakes up when it gets sun

    Knowing the way that western organizations build spacecraft and that it was built by Germans, I imagine there will be some time millennia from now the comet beaks from our star system and finds itself orbiting some star, waking up, and freaking the hell out of some sentient beings on another planet.

    1. Anonymous Coward

      Re: Wakes up when it gets sun

      Nah, it will be found by the sentient machine planet that made V-ger, and once reequipped with a new planet-cracking antimatter drill it will go out into the cosmos looking to harvest organic matter from inhabited planets. Oops!!

    2. werdsmith Silver badge

      Re: Wakes up when it gets sun

      "Knowing the way that western organizations build spacecraft and that it was built by Germans"

      The Rosetta bit, that worked properly, was built in Stevenage, Hertfordshire.

      The mission plan always had to trust to a big slice of luck, though they could have done a lot better with the gas landing thrusters and the harpoons.

      1. Anonymous Coward
        Anonymous Coward

        Re: Wakes up when it gets sun

        @werdsmith: You know, I am French, living in England, and I heard the same bullshit when I was in France at the time. I am pretty sure the German in Darmstadt and probably serve the same stuff "we made it happen".

        The reality is that talent does not have any border or nationality (a bit like stupidity), and without talent from everywhere on Earth, *humanity* would not be able to achieve this.

        A few facts for you:

        - developer: ESA, 20 nations (see France and Germany are by FAR the biggest contributor financially speaking Headquarter in Paris, mission control for Rosetta in Darmstadt.

        - launcher: Ariane, launched from Guyanne, French territory, and also international project. Biggest shareholder is France, but hey, it's nice to collaborate with talented people.

        - Rosetta: See for mode details

        - Rosetta Instruments: ALICE+MIRO+IES (Nasa), Osiris (German consortium led by Max Planck Institute)... do yo want me to continue?

        - Philea: APXS (Germany), CIVA+CONSERT (France), ... do you really want me to get there?

  3. Osgard Leach

    So still room to improvise and you can't ask for much more after a landing like that.

    Oh Beagle 2, Beagle 2, where was your luck?

  4. Longrod_von_Hugendong

    What a shame...

    it just didn't quite go to plan, but I am sure some science will be done - and at the end of the day, just go for it, try moving position, you have nothing to lose.

  5. Glen 1

    Still alive

    A lot of the lyrics ring true here :)

    Look at us talking when there's science to do!


    1. Scott Broukell

      Re: Still alive

      Indeed, I wonder if the folks at ESA are "Philaen Groovy" right now.

  6. Mark Allen

    One leg in the air?

    In the air? Really? Where did it find some "air"?

    1. alain williams Silver badge

      Re: One leg in the air?

      It is looking for a lamp post to pee on -- wouldn't you be after 10 years ?

      1. Mark Allen

        Re: One leg in the air?

        > It is looking for a lamp post to pee on -- wouldn't you be after 10 years ?


        Isn't that going to pollute the samples they want to take? I would have hoped the lander was told to go before landing.

  7. Elmer Phud


    Blimey, there are people in Blighty that can't get that.

    1. Yer Mother You Will

      Re: 26k?


  8. codejunky Silver badge


    Even the lander had a spring in its step!

    On a serious note woohoo it made it!

  9. Daz555

    It will be a great shame if after 10 years and 6 billion kilometres it only gets to party on the comet for 64 hours.

    Hopefully it's final act before it dies will be to chance one leap into the unknown!

    1. Alan Brown Silver badge

      "It will be a great shame if after 10 years and 6 billion kilometres it only gets to party on the comet for 64 hours."

      Huygens (the Titan probe) got less than 64 minutes before it froze to death.

      1. Bleu

        That is differemt

        and only comparable to the Soviet Venera probes, which did similarly well in surviving an incredibly inhospitable environment.

        My vote is for the Venera project as all-time most wonderful automated missions to another planet, but Huygens was also wonderful.

        Curiosity, fantastic landing technique, breathtaking, and unlike Rosetta's boxy little spawn, worked at every step on a much more difficult sequence.

  10. Peter Simpson 1

    Hell of a job, my hat's off to those folks.

    SPB is taking notes, I hope?

    (having had some experience with missions that dind't go quite as planned)

  11. 0laf

    Well it sounds like they'll be able to do some work then take a chance either on drilling, harpooning, harpooning and drilling or bouncing.

    Still it's on a fricking comet. Pints have been earned.

    1. Pedigree-Pete

      Weldone ESA, but fluid units dear OP?

      Stuff yer Pints, they'll be drinking in Litres.

    2. Anonymous Coward
      Anonymous Coward

      Brian Aldiss

      often a rather brilliant English SF writer, places an entity called Canquistidor in at least a couple of his stories.

      Visitors to Europa (the one revolving around Jupiter) find edible seafood in the alleged ocean there, commercial interests (Canquistidor) arrive to wipe them out, then find more further away, and so on.

  12. Anonymous Coward

    Well, I hope they work things out and can sample the comet!

    This is what you get for buying your harpoon system from Wal-Mart!!

    1. Jim E

      Re: Well, I hope they work things out and can sample the comet!

      I'll have you know that Walmart harpoons come with the best of testimonials, from some whaling captain, name of Ahab.

      1. Graham Dawson Silver badge

        Re: Well, I hope they work things out and can sample the comet!

        Don't knock it, those harpoons held him pretty firm to the side of the whale as I recall, at least in the film.

        1. Destroy All Monsters Silver badge

          Re: Well, I hope they work things out and can sample the comet!


          Sorry, I mean ... finance IMMEDIATELY a second mission with my dear TAX EUROS instead of feeding them into maw of entitled civil euroserpents (who permanently detect "austerity" == a conspicious failure to upgrade their paycheck for now particular reason)

      2. JetSetJim

        Re: Well, I hope they work things out and can sample the comet!

        According to xkcd, there're probably no whales on the comet, so that's where they went wrong.

  13. Anonymous Coward
    Anonymous Coward

    I wonder if,

    They could PWM the drill in such a way that the acceleration/deceleration is enough to put a minute turning moment into the craft?

  14. Michael Thibault

    I wonder if the harpoon could be used to launch Phil off of the comet's surface--after doing as many of the experiments as possible within the first battery charge period, and with consideration for the need of direct contact with the surface for those. If the harpoon can be fired, and Phil relaunched with some chance of having another go at a 3-point landing, somewhere else and sometime later... Could turn into an interesting, challenging long-distance hobby.

  15. daveyclayton

    It has harpoons? Bad ass.

    1. Anonymous Coward
      Anonymous Coward


      It was only halfway through today that I suddenly twigged what the reference to Whales on yesterday's XKCD cartoon was about.

      1. Martin Budden

        Re: Harpoons

        You should go through the entire sequence of yesterday's XKCD images (about 60 I think) from start to end. Then you'll understand fully how the whale reference started.

  16. GrumpenKraut

    Fingers crossed...

    Fingers FIRMLY crossed!

  17. Anonymous Coward
    Anonymous Coward

    Hopefully they remember to drill down at least 800ft before detonating the nuke, otherwise the two halves will fail to miss the earth...

  18. lidgaca

    They were never going to be able to drill without Bruce Willis on board.

  19. Anonymous Coward
    Anonymous Coward


    ¤ The lander landed.(It did not bounce off into space.)

    ¤ In an orientation at least semi-usable. (It did not end up upside down.)

    ¤ It does send flawless, nay, magnificent images. (It did not break / dust shut its cameras.)

    ¤ It is sending at least some scientific data. (It did not remain silent.)

    ¤ While the solar panels may not be be able to perform as hoped for (we never could be sure anyway, because of possible dust), the batteries do work and allow some time to do science. (They did not break or go flat in The Bouncing.)

    All this on the first try.

    Over the time of a decade.

    And the distance of almost half a light hour.

    Let's be happy!

  20. Colin Ritchie

    We hit something the size of South London from 10 years away.

    This in itself is cause for jubilation.

    1. SkippyBing

      Re: We hit something the size of South London from 10 years away.

      So better than most air forces...

    2. Anonymous Coward
      Anonymous Coward

      Re: We hit something the size of South London from 10 years away.

      Aren't there some parts of South London that could stand being hit?

  21. noominy.noom

    More Kudos

    I've already posted congratulations but I think ESA deserve some more. Fantastic stuff. I hope they stay in the game and do more projects in the years to come.

  22. Slx

    It's actually not German, it's very much pan-European

    It's very very much a product of European engineering.

    Austria, Belgium, Finland, France, Germany, Hungary, Italy, Ireland, the Netherlands, Poland, Spain, Switzerland and the United Kingdom all contributed pretty serious technology to it.

    Europe has shed loads of technology when you bring it all together. We should be doing more of this kind of stuff and less wrangling with unruly banks that cost us hundreds of billions !

    1. SteveCarr

      Re: It's actually not German, it's very much pan-European

      And bits from New Zealand as well - Rakon crystals are used in there somewhere...

  23. Canocola

    So it turns out that landing on a comet is harder than expected, and not necessarily for the reasons we expected either. That sounds like a pretty important result for doing this sort of stuff in future (the practical difficulties with coping with tiny amounts of gravity should certainly give any asteroid hunters food for thought). It also looks like our thinking about comets needs a shake-up. We knew from Rosetta that this was a weird shape, from Philae we also learn that it's heterogenous in its solidity - something that wasn't obvious from the photos. This mission already looks like it will leave more questions than answers, and that seems even more exciting than simply ticking the boxes of what we thought we knew.

    1. Alan Brown Silver badge

      "the practical difficulties with coping with tiny amounts of gravity should certainly give any asteroid hunters food for thought"

      There's already been one asteroid landing. Unfortunately it was too late to inform philae development and it didn't have legs or perform sampling, so stability wasn't a consideration (it was flown on using ion engines)

    2. Bleu

      Japan space agency's

      failure with Hayabusa in a similar micro-gravity environment already demonstrated the difficulty.

      The lander failed.

      The main probe did get there and back, pretty great, but it didn't manage to get much in the way of samples. A similar technical failure.

  24. ascii bandit

    ...pan european... Denmark too

    The PSU is made in Denmark

  25. DocJD

    Two Legs

    How does it keep from tipping over if only two legs are on the "ground?"

    1. Destroy All Monsters Silver badge

      Re: Two Legs

      Lack of gravitas.

  26. Anonymous Coward
    Anonymous Coward

    Philae has not so much landed as matched orbit at zero altitude. The ice screws, harpoon and top thruster were all intended to assist in the process of sticking it to the surface in the absence of gravity and uncertainty about the surface conditions. Two of those systems did not work as planned, and without the top thruster, firing the harpoon again could send it skittering about and out of contact with the comet. They will take that risk when they believe it is worth it - until then, science.

    1. Old Handle

      It's semantics, but I don't know if I could really agree the first sentence. As I understand it, gravity is the only thing holding it in place. I mean, it bounced and came back down. That sounds like a landing to me. But I do of course agree that the situation is precarious. Doing anything rash could easily make it "jump" and even if it didn't achieve escape velocity (estimated to be 1 m/s) it might not be so lucky to land mostly right-side-up next time.

      1. werdsmith Silver badge

        If the thing is in contact with the body of the comet then there is a contact or frictional component.

        I don't believe that there was an orbital component to the Philae flight, I assume the reason that it moved 1km from its original contact location is because it bounced and the comet rotated a bit before it came back down. So now the Philae is in a fixed spot on the comet body, the comet must be taking it round with its own rotation.

  27. Slx

    The ESA has a significant but small budget compared to NASA.

    €4.28 billion (about $5.51 US)

    NASA has budgets of around $18.4 billion or so.

    ESA Membership:

    Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, Netherlands, Norway, Poland, Portugal, Romania, Spain, Sweden, Switzerland and the UK are all the current members.

    Canada's had associate membership since 1979 and the European Union itself is also a member and contributes quite a bit of the cash (slightly less than France and Germany though)

    Total cost to Europeans on average €3.50 each or 20 cents per year for the duration of the Rosetta programme.

    Seems like value for money, considering I lost many times more than that down the back of the sofa this week alone.

    1. Alan Brown Silver badge

      "The ESA has a significant but small budget compared to NASA."

      And NASA's budget is smaller than the amount the US military spent on air conditioning in Iraq.

      The amazing thing about space exploration is that so much gets achieved on so little budget.

  28. willi0000000

    Just because i'm a left-ponder doesn't mean i think we could have done as well or better.

    when you think of the number of ways the landing could have gone wrong that would have resulted in the complete destruction of Philae, what happened is just amazing . . . it sits precariously but apparently stable and can carry out most of the science planned for it. just wow!

    i don't think the harpoons can be used to kick Philea off the surface as they seem to be (pun semi-intended) a one-shot deal but the landing legs can flex because, way back when, some bright thing said "why don't we add the capability for a 'hop' just in case we need it?" if Philea is on the side of a cliff with it's one leg in space on the 'up' side relative to the local topography hopping with the other two legs may impart enough rotation to allow landing upright on 'flatter' ground and out in the sun.

    i'm not counting the Flight Dynamics people out on this one yet . . . but i'll bet they thought they were going to get some sleep after the (first) touchdown.

    two years to run on the whole mission, lots more to see and learn . . . incredible job so far and i look forward to closeup pictures of gas geysers and flying debris as 67P warms up.

  29. ColonelDare

    To 32,767 and beyond!

    All done with a 1980's Harris RTX2010 processor, 16 bits, running at 8Mz, programmed in Forth.

    Well two of them actually - one on Rosetta, one on Philae.

    So now I have loaded gForth onto my 32 bit 900 Mhz Raspberry Pi, and with access to a mountain of my kid's lego all I need is an Ariane 5 and a depth space tracking network..... :)


    1. werdsmith Silver badge

      Re: To 32,767 and beyond!

      "All done with a 1980's Harris RTX2010 processor, 16 bits, running at 8Mz, programmed in Forth."

      I'm still waiting for the radiation hardened Raspberry Pi.

      Lack of complexity on the RTX2010 has got to be a big advantage.

      1. ColonelDare

        Re: To 32,767 and beyond!

        Yeah - but with 1080p full HD video it would be worth it ;)

        Errrr... but I need a longer HDMI lead!

  30. Conundrum1885

    RE. Re. To 32,767 and beyond!

    1990 called, they want their dialup back.

    What about just using four Pi's in a quorum sensing arrangement?

    With separate power controllers and self reloading code from a backup flash chip so they can self repair?

    (wonders if Pi's are actually that sensitive to radiation, maybe we should start a Kickstarter "Send Pi to ISS" ?)

    1. Bronek Kozicki

      Re: RE. Re. To 32,767 and beyond!

      There is not much radiation in ISS, otherwise people wouldn't be living there. It is much, much worse away from planets, where Philae and Rosetta are at this moment.

      Would be nice to have radiation hardened system-on-chip similar to ARM7, but this is not going to happen in a hurry.

      1. Yer Mother You Will

        Re: RE. Re. To 32,767 and beyond!

        I wonder if you know how they harden integrated circuits against radiation? I do. You might go and do some research, just as I did, then you would know what I know. Americans, huh!

    2. gerdesj Silver badge

      Re: RE. Re. To 32,767 and beyond!

      "wonders if Pi's are actually that sensitive to radiation" - put it in a microwave and report back.



      1. Conundrum1885

        Re: RE. Re. To 32,767 and beyond!

        Microwave, no. (remember the Iphone 6 fiasco)

        Radiation source, HELL YEAH.

        Just need to make one using all the bits I have, put it in a lead box with the calibrated source on the chip and a heatsink with thermal monitor then see how many soft errors it gets over say a month doing a simple task like processing video data.

        Wonder if this is the most creative use for a Pi yet?

  31. Andy Davies

    bounced and re-landed

    Great effort, but I was a little surprised that it re-landed - I would have thought that 1m/s would be above escape velocity (the first bounce speed according to TV reports). No maths, just my wag.

  32. Bartek

    The comet is heavier now. how will it affect its course ?

    Just hope they planned for that extra mass on the rock wont put it in our path.

    1. Craig 2

      Re: The comet is heavier now. how will it affect its course ?

      Yes, but the Earth is lighter by the mass of the probe so it all cancels out! :P

  33. Billa Bong

    Speedy comms

    "They were also thrilled that the comms link with Rosetta and Philae was working so well, pushing scientific data back to Earth at around 26Kbps."

    So about the same speed as my super-fast broadband then. #fuming-at-rural-adsl

  34. Stevie


    So, despite the downvotes and snarls I got for saying so, the lander is down DESPITE the design engineering, which can be summed up as:

    Anti-Recoil Thruster System - Fail

    Harpoon Landing System - Fail


    Screw Piton Lander Securing System - Fail

    and thanks to all the above

    Primary comet analysis-thru-drilling mission - Fail.

    Telemetry will be interesting of course, assuming the lander can maintain power enough to provide it, and I look forward to the time when the so-called scientists get bored enough to launch Mission Spacehopper which will definitely be a first. Perhaps the lander ought to be rechristened "Mario" in an effort to lure in the Luck Gods. Even now I suspect they are feverishly concocting a mission goal to justify doing it. Let's hope the gear retracts don't seize up in the meantime.

  35. geezer88

    With one leg in the air - - -

    at least it will be able to pee on the nearest fire plug

  36. Bleu


    So many reg commentards made nasty comments about the failure of Phobos to ground, it is hard not to enjoy the failure of this.

    Harpoons didn't fire, thruster didn't work.

  37. Conundrum1885

    Re. Shadenfreude

    Expecting report back from USPS. "While you were out..."

    Re. solar panels, what about just aiming a moderately powerful IR laser at it?

    Ought to give the panels a bit of a boost and provide an excellent range test on the SDI platform the 'Merkins don't officially have.

  38. Bleu

    Brian Aldiss

    often a rather brilliant English SF writer, places an entity called Canquistidor in at least a couple of his stories.

    Visitors to Europa (the one revolving around Jupiter) find edible seafood in the alleged ocean there, commercial interests (Canquistidor) arrive to wipe them out, then find more further away, and so on.

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