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Space Mars

Schiaparelli Mars Probe's Parachute 'Jettisoned Too Early', Whereabouts Still Unknown (bbc.com) 185

An anonymous reader writes: Europe's Schiaparelli lander did not behave as expected as it headed down to the surface of Mars on Wednesday. Telemetry data recovered from the probe during its descent indicates that its parachute was jettisoned too early. The rockets it was supposed to use to bring itself to a standstill just above the ground also appeared to fire for too short a time. The European Space Agency (Esa) has not yet conceded that the lander crashed but the mood is not positive. Experts will continue to analyse the data and they may also try to call out to Schiaparelli in the blind hope that it is actually sitting on the Red Planet intact. In addition, the Americans will use one of their satellites at Mars to image the targeted landing zone to see if they can detect any hardware. Although, the chances are slim because the probe is small. For the moment, all Esa has to work with is the relatively large volume of engineering data Schiaparelli managed to transmit back to the "mothership" that dropped it off at Mars - the Trace Gas Orbiter.
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Schiaparelli Mars Probe's Parachute 'Jettisoned Too Early', Whereabouts Still Unknown

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  • by Salgak1 ( 20136 ) <salgak.speakeasy@net> on Thursday October 20, 2016 @09:15AM (#53114667) Homepage

    . . .there were two failures: the parachute release and the burn length. But both were likely set in the software on the lander, so I suspect parameters got borked somehow.

    Additionally, if the burn was shorter than planned, that would put significantly more fuel on board when the catastropic 'landing' occured. Which, depending on the propellant, could have caused an explosion at the crash site. That would likely scatter the remains, but should leave a notable mark on the soil. . .

    • by idji ( 984038 ) on Thursday October 20, 2016 @09:43AM (#53114845)
      I suspect something happened to the parachute just before jettisoning - e.g. rope breaking/twisting, chute tearing/burning that caused the lander to tumble, and so the rockets switched off as they weren't pointing against the forces on the lander that the accelerometers were reading.
      Look at JPL's Mars parachute test in 2014 that ripped the parachute https://www.youtube.com/watch?... [youtube.com].
      • by Rei ( 128717 )

        That wouldn't explain why the parachutes were jetisoned. They shouldn't have jetisoned at that point in time.

    • by The Raven ( 30575 ) on Thursday October 20, 2016 @09:46AM (#53114869) Homepage

      I wonder if the burn was shorter than planned because the ground came up and interrupted it... a likely possibility if the parachute released too early and snapped off. I've seen this happen before... in KSP.

      • by Tablizer ( 95088 )

        because the ground came up and interrupted it

        So it wasn't properly grounded.

      • by joh ( 27088 )

        There were 12 seconds of signal after the engines shut off. Looks more as if the lander was in free fall and then impacted after these 12 seconds.

      • by Solandri ( 704621 ) on Thursday October 20, 2016 @12:55PM (#53116445)
        The burn cut off 19 seconds before loss of signal, so the probe was in freefall for at least 19 seconds. From TFA:

        Not only is the chute jettisoned earlier than called for in the predicted timeline, but the retrorockets that were due to switch on immediately afterwards are seen to fire for just three or four seconds. They were expected to fire for a good 30 seconds.

        In the downlinked telemetry, Schiaparelli then continues transmitting a radio signal for 19 seconds after the apparent thruster shutoff. The eventual loss of signal occurs 50 seconds before Schiaparelli was supposed to be on the surface.

        That last sentence, if you assume loss of signal corresponds to impact with the ground, suggests de-orbit velocity relative to the ground was much higher than expected. The early parachute release may have been the culprit. Or the probe entered the atmosphere at too steep an angle (which could also explain the early parachute release - the probe would've entered higher density atmosphere more quickly thus increasing aerodynamic load on the chute to the point at which it failed). The burn probably began at a higher velocity than it was designed for.

        If we're speculating, my guess would be the higher velocity when the retro-rockets were fired caused greater instability - aerodynamic forces caused the probe to rock more than expected. The parachute's purpose isn't just to slow the craft down; it also keeps the craft's orientation stable during this period of higher aerodynamic forces. Without it, drag on tiny asymmetries on the front of the craft can result in large turning moments. With a parachute attached, these moments are countered by the righting moment the parachute imparts on the rear of the craft every time it deviates from the proper orientation. Without the parachute, the craft can experience large oscillations or even flip due to these drag-induced turning moments. The large amplitude and higher frequency of the resulting oscillations could've exceeded what the rocket control software was designed to handle, and it shut off prematurely when it exceeded some threshold programmed into the software.

    • by Kjella ( 173770 )

      there were two failures: the parachute release and the burn length. But both were likely set in the software on the lander, so I suspect parameters got borked somehow.

      As in hardcoded on a timer? Unlikely. This is quite far into the descent and the parachute was probably supposed to jettison when a certain altitude/velocity was reached. That both the parachute and thusters was off suggests to me a sensor failure led the probe to think it was going much slower or flying much lower than reality. It would be odd for both systems to fail and at the same time be in good enough condition to send radio signals.

    • Additionally, if the burn was shorter than planned, that would put significantly more fuel on board when the catastropic 'landing' occured. Which, depending on the propellant, could have caused an explosion at the crash site. That would likely scatter the remains, but should leave a notable mark on the soil. . .

      Maybe America could send its rover around to take a look - a nice explosion on the surface might uncover evidence of water. Or it could just clean up the debris.

    • by jsrjsr ( 658966 )
      Or maybe the propellant leaked away and there was only enough left for a few seconds?
    • Sigh......they shouldn't have used metric.
    • Re: (Score:2, Funny)

      by Anonymous Coward

      To recycle the old joke, "There are two kinds of countries: the kind that use the metric system, and the kind with successful Mars rovers."

  • by Anonymous Coward on Thursday October 20, 2016 @09:26AM (#53114733)

    Yeah, I do this all the time in Kerbal Space Program. From my experience, they just need to make sure the parachute icons aren't red or yellow when they deploy them. It always sucks to go through a whole mission only to mess up your landing and waste everything. I suggest they revert to launch and try again.

  • Repeating itself (Score:4, Insightful)

    by TWX ( 665546 ) on Thursday October 20, 2016 @09:35AM (#53114795)
    Isn't this essentially what happened to Mars Polar Lander? Incorrect sensory interpretation leading to the computer taking the wrong actions, thinking it was on the ground when it wasn't?
    • by Tablizer ( 95088 )

      essentially what happened to Mars Polar Lander? Incorrect sensory interpretation

      The name confused the math team; they accidentally used polar coordinates.

    • No, you're thinking about one of the Die Hard movies.

      • by TWX ( 665546 )
        Poor Lt. O'Brien... He dies in almost all of the movies that aren't *Star Trek*.
  • by I4ko ( 695382 ) on Thursday October 20, 2016 @09:56AM (#53114943)
    The Martian society salutes you. Job well done.
  • by idji ( 984038 ) on Thursday October 20, 2016 @09:56AM (#53114945)
    I was very disappointed and angry at the ESA Press Conference this morning. Last night when they suspected (knew) [There is no way this landing was designed to not return a success signal immediately] the Lander had crashed they silenced everyone and announced a press conference at 10 AM the next morning.
    At the Press Conference they emphasised the success of the orbiter and mentioned NOTHING at all about data from the lander. They left that all to questions from the Press. Basically all questions from the Press were about the lander and the data (and they were good questions - no stupid questions came), and they drip fed a piece of info at a time to the journalists.
    I believe the suits at ESA were in damage control because they are scared about losing funding for the 2020 lander so they mentioned NOTHING about the crashed lander, so that when politicians check on the press releases/conferences in months to come there is NO info on the crash, but in a few days the world will know anyway, especially if NASA gets a photo of the impact and debris.
    They did not make any statements at all (e.g. yes we got data from the Lander, the rockets fired for only 3-4 seconds, something went wrong with the parachute and we suspect a very hard landing) in a controlled and orderly way, they forced the journalists to extract it from them relunctantly.
    I was super disappointed about scientists playing politics and covering up what they obviously knew the audience wanted to know. It was sickening.
    And, yes, I live in Europe and yes, I want my tax Euros to fund the 2020 Lander, but I'm angry at scientists playing politics and ignoring the audience who wanted to know what happened last night and they deliberately said nothing.
    • by MetalliQaZ ( 539913 ) on Thursday October 20, 2016 @10:21AM (#53115137)

      It is possible that they wanted to have completed some kind of analysis to determine exactly what happened before they started talking about it.

      • by Tablizer ( 95088 )

        It is possible that they wanted to have completed some kind of analysis to determine exactly what happened before they started talking about it.

        This is Murica, we guess quickly, and talk out of our ass.

    • Re: (Score:3, Insightful)

      by Anonymous Coward

      I've only been part of 30 or so aircraft mishap investigations, but I'm sure that in the space world, where you only have telemetry, none of that confusing physical evidence, that you can perform an accurate mishap analysis in 45 minutes. Seriously, all the rest of that time is just bullshit to cover people's asses, right? I mean, we already know all of the possible failure modes, and deliberately didn't design around them, so it's just a matter of pasting a few hundred megabytes of data still getting trans

    • I was super disappointed about scientists playing politics and covering up what they obviously knew the audience wanted to know.

      Working in a U.S. National Lab, I can say with some likelihood of correctness that any scientists speaking in front of cameras were almost certainly having their strings pulled by the hidden suits in Management, a separate division. So while it might have seemed like scientists were covering their tracks, they almost certainly would have lost their jobs if they'd been open, honest, and forthright without Management's vertiginous spin.

      (And, any scientists that should lose their jobs over confusing seconds wi

    • I believe the suits at ESA were in damage control because they are scared about losing funding for the 2020 lander so they mentioned NOTHING about the crashed lander, so that when politicians check on the press releases/conferences in months to come there is NO info on the crash, but in a few days the world will know anyway, especially if NASA gets a photo of the impact and debris.

      The ESA in general seems to hold their cards a lot closer than NASA. I suppose there are cultural or political reasons like you suggest, but it's annoying if you're used to the flood of information NASA releases.

  • This [vice.com] was the worst.
  • And you can probably blame the metric system since the landing rockets fired for only 3 seconds instead of 30 - that 10x stuff makes everything look too simple
  • Comment removed based on user account deletion
    • by Octorian ( 14086 ) on Thursday October 20, 2016 @10:57AM (#53115419) Homepage

      Only thing crazier, would be to put balloons around a lander and let it bounce to a landing. Could you even imaging such a thing?

      Ahh yes, Pathfinder, Spirit, and Opportunity :-)

    • Bubble wrap is a mature (and fun) technology used for safeguarding fragile objects from damage suffered by falling to the ground. Wrapping a lander in balloons is just a generalization of that technology ;)
    • by joh ( 27088 )

      Viking 1 in 1976 landed exactly like Schiaparelli and it worked fine, at the first try. Heat shield, parachutes, landing rockets, touchdown. Worked for years, too.

      Mars is hard, but it seems to be harder for some than for others.

    • When I saw the video of the "7 minutes of Terror" and the crazy landing system for Curiosity, I thought, "Seriously, all of these mechanisms are required?".

      Then I saw the Schiaparelli, landing, and I thought, "can the do this successfully in what appeared to be a more 'straight-forward' approach?"

      We now, it appears, know why Curiosity had the landing system designed the way they did. Only thing crazier, would be to put balloons around a lander and let it bounce to a landing. Could you even imaging such a thing?

      Yes, that's the trouble with the Martian atmosphere, enough to make landing by rockets problematic but not enough to slow things down. I remember reading an article where a guy that works specifically on parachutes for re-entry vehicles said that a parachute only landing on Mars was not possible. Keep making the parachute bigger and you end up with deminishing returns for weight and other reasons before it will slow things down enough. Likewise, supersonic entry into an atmosphere with rocket tech at the ti

      • When dealing with a human landing on Mars and you are talking something like 40 tons

        This obesity thing is really getting out of hand.

  • It's too bad budget cuts in the US forced JPL to back out of the program. While the US has several spectacular failures, they also have even more successes. The fact that they got the Rube Goldberg landing device for the Curiosity lander to work is an engineering wonder in itself. Hopefully Europe has the same tolerances for learning from mistakes as the US.

    • It's too bad budget cuts in the US forced JPL to back out of the program. While the US has several spectacular failures, they also have even more successes. The fact that they got the Rube Goldberg landing device for the Curiosity lander to work is an engineering wonder in itself. Hopefully Europe has the same tolerances for learning from mistakes as the US.

      [badjokeeel] It sounds to me like JPL pulled out just in time.[/badjokeeel]

  • Maybe start with the Beagle 2, maybe they are cozying up together? ;)

  • Don't worry. They won't feel a thing during the landing.

  • It may be a problem with the Matrix [theonion.com]

  • Re: (Score:2, Insightful)

    Comment removed based on user account deletion
    • TFA has a graphic showing landing locations for the various probes. From an analysis of the pixels, it appears that Opportunity and Schiaparelli landed in the same location. Of course, by now Opportunity is halfway up Olympus Mons, but maybe it could look behind itself and find the hydrazine cloud.

  • So what if the parachutes deployed too early? So long as they deployed, one would assume they they would do their job regardless (eventually). Unless of course there were also parameters to detach and eject the parachutes just prior to landing or rocket burn. Perhaps having the Parachutes deploy so early slowed the craft so much that only a very short burn was even required to land safely.

    The optimist in me likes to think that in doing so, about the only thing that might be causing the "delay" is that I bel

  • by dmaul99 ( 1895836 ) on Thursday October 20, 2016 @11:50AM (#53115843)

    So the emergency lithobraking maneuver didn't do the trick then. This sucks. Really.

  • "Whatâ(TM)s this thing suddenly coming towards me very fast? Very very fast. So big and flat and round, it needs a big wide sounding name like ⦠ow ⦠ound ⦠round ⦠ground! Thatâ(TM)s it! Thatâ(TM)s a good name â" ground!

    I wonder if it will be friends with me?"

  • Where's Matt Damon when you need him?

Things are not as simple as they seems at first. - Edward Thorp

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