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Space Science Technology

Beagle 2 Failure Theories 254

Dan East writes "New Scientist has an article discussing the failure of ESA's Beagle 2 Lander. Theories as to why the landing failed include thinner than expected upper atmosphere, extreme atmospheric temperature fluctuations, and possible physical damage to Beagle 2 seen in an image acquired immediately after it separated from Mars Express. Recent data acquired by Mars Express, as well as NASA's Mars Rovers, are helping direct investigations into the failure. So far only around half of Beagle 2's landing ellipse has been imaged in an attempt to locate remnants of the lander. USA Today is also running an AP story on these latest theories."
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Beagle 2 Failure Theories

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  • by flewp ( 458359 ) on Tuesday March 09, 2004 @01:57AM (#8507151)
    There is probably more than one answer/reason.

    The first thing that springs to mind is that any kind of wiper wiping dust across could scratch the panels

    Wipers are also one more (well, more than one) mechanical part to go wrong, and also add weight.

    Perhaps radiation, and other things would limit the life of the rover to just over 3 months and the wipers were deemed unnecessary. Basically what you're saying in the last paragraph.

    The most likely scenario is that the scientists and engineers, with much more knowledge and experience in this type of thing know what they're doing and have determined for some reason wipers aren't a possibility. I highly doubt it's something they've overlooked.
  • by Anonymous Coward on Tuesday March 09, 2004 @02:01AM (#8507185)
    Ok, this questions is *always* a popular one when talking about rovers on mars, and the solar panels that tag along with them. The reason that the panels can't use wipers to wipe the dust of is because the dust is electrostatically charged. Using the wipers would scratch the hell out of the panels, making them usually for gathering any more photons.

    -brandon
  • by aluminum_geek ( 756252 ) on Tuesday March 09, 2004 @02:04AM (#8507207)
    It appears that dust covering the solar panels is only one of a number of factors which will end up rendering the mars rover a paperweight.
    The dust on the solar panels appears to be complicated by the fact that the batteries "lose capactity" and (probably most importantly) the sun moves past the latitude where the rover is located. Just like days get shorter in the winter...

    I guess it doesn't matter if your solar panels are clean if they aren't being exposed to the sun for an appreciable length of time.

    All of this was grossly overinterpreted from an article lean on details... http://marsrovers.jpl.nasa.gov/mission/tl_surface. html [nasa.gov]
  • by subtropolis ( 748348 ) on Tuesday March 09, 2004 @02:08AM (#8507229)
    This was discussed [slashdot.org] the last time there was an article about the (NASA) rovers. There were a lot of suggestions and even more reasons why they weren't very good solutions

    The curator said that "five hundred people" before me had asked the same question

    I'm hoping the next rover (or the next one to built) will sport some elegant new hack suggested by some Jane Average.

  • by York the Mysterious ( 556824 ) on Tuesday March 09, 2004 @02:09AM (#8507244) Homepage
    NASA addressed this during the launch. They tried a lot of different methods of wiping the solar panels and found out it just wasn't cost effective to make something that would work. It added a ton of bulk and was prone to breakage. Hope that helps.
  • by Anonymous Coward on Tuesday March 09, 2004 @02:11AM (#8507253)
    From what I read, they didnt fully test Beagle. I believe NASA found out that their parachute didnt work for the rovers in the beginning, and they tested at Ames Research wind tunel. I bet the same with Beagle. The parachute didnt work and probably shred into pieces. Of course if the parachute is shredded, the Beagle probably did land about 25 feet beneath the martian soil :D
  • by Molina the Bofh ( 99621 ) on Tuesday March 09, 2004 @02:14AM (#8507274) Homepage
    They did think about it. But it wouldn't be practical, or worth it.

    It's actually a FAQ.

    I suggest you read
    This [discovery.com]
    and this [sorrab.com]
  • by fenix down ( 206580 ) on Tuesday March 09, 2004 @02:28AM (#8507351)
    I'd guess that really wiping dust off would scratch the panels, maybe only a little, but enough that it's better to just let the single grains accumulate instead of long scratches. But you'd think if Lens Crafters can make scratch-resistant plastic NASA could too...

    Ok, I looked up how Pathfinder died, and it looks like the lifespan on the rover there was dictated by how many day/night temperature changes the electronics could take. I'm guessing that they just can't get a circuit board to put up with that, so everything else only has to last as long as a bit of solder that somebody's popping in and out of a freezer every 12 hours.
  • Re:Money (Score:4, Informative)

    by nastyphil ( 111738 ) on Tuesday March 09, 2004 @02:29AM (#8507359)
    The Beagle2 lander was a small part of the overall mission. It was the result of an opportunity ('scuse the pun)later in the Mars Express project to tack an extra mission onto the mission platform. The process of obtaining detailed imaging of the surface of Mars is far, far more than "nothing to show for it except for failure." Have a look at the ESA page about the mission for more information.
  • by jelle ( 14827 ) on Tuesday March 09, 2004 @02:30AM (#8507368) Homepage
    CNN [cnn.com] has the scoop.
  • Re:Money (Score:3, Informative)

    by gad_zuki! ( 70830 ) on Tuesday March 09, 2004 @02:35AM (#8507398)
    >they decided to waste 370 million

    The beagle2 cost about $60 million.

    Opportunity and Spirit cost $820 million dollars.

    >We also spent over twice as much as they did.

    Nope, about 12 to 14x what the US spent.
  • by anno1602 ( 320047 ) on Tuesday March 09, 2004 @03:05AM (#8507538)
    RTFA. The point is that this data is inaccurate, because the atmosphere shows hitherto-unkown extreme fluctuations of pressure and temperature. It was not a problem for the NASA landers which decelerated on rockets, but it could have been a problem for Beagle since it relied on parachutes to turn a fall into a landing.
  • by djupedal ( 584558 ) on Tuesday March 09, 2004 @03:09AM (#8507557)
    http://www.cnn.com/2004/TECH/space/03/08/mars.beag le.reut/index.html
    ==================
    Possible sighting of Beagle probe

    Monday, March 8, 2004 Posted: 6:43 PM EST (2343 GMT)

    LONDON, England (Reuters) -- Beagle 2, the British space probe which disappeared as it descended towards Mars, may have been spotted on the surface of the Red Planet, scientists say.

    No signal has been received from the craft since it was due to land on Christmas Day last year, despite various attempts by Mars orbiters and telescopes on Earth to make contact.

    But photographic images of the area where Beagle 2 was to have come down show four bright spots, dubbed a "string of pearls" by scientists, which may be the remains of the probe.

    "It could be the lander with its air bags and parachute," said Lutz Richter from the German Aerospace Center, who helped plan the Beagle 2 project as part of Europe's first solo mission to another planet.
  • According to CNN (Score:3, Informative)

    by Snuffub ( 173401 ) on Tuesday March 09, 2004 @03:18AM (#8507580) Homepage
  • by NewtonsLaw ( 409638 ) on Tuesday March 09, 2004 @04:15AM (#8507812)
    (1) In Formula-1 racing, the helmets have visors that are covered with clear plastic tear-off sheets. Instead of wiping their visor if they get dirt on it while they're in the middle of a race, they just tear off the topmost sheet and they're good to go

    This might be a viable option -- but then again it's possible that the sheets could tear or jam in such a way as to produce a high degree of reflection and significantly reduced array efficiency. It's just another point of failure.

    (2) Pick the dust up. They make simple electrostatic floor cleaning brushes here on earth (as seen on TV) that pick up dust like nobody's business

    Possible -- but it would also require the creation of a high-voltage charge -- and the other sensitive electronics onboard may not like that kind of charge. The high levels of ionizing radiation on the surface of Mars may also affect the operation of such devices.

    (4) Gently blow atmospheric air across them. Small motor, high speed fan, nozzle directing the air across the surface. Probably won't work well on Mars with the thin atmosphere

    Wouldn't even work on earth with its comparitively dense atmosphere. Haven't you noticed that even if you take a dusty car for a high-speed run at 100mph or greater, it's still covered in dust when you stop? Do a google on "boundary layer" and "laminar flow" to find out why this method won't work with very small dust particles.

    (5) The system that deploys the solar panels could be designed so that the action of deploying them passes the panels past the cleaning apparatus. This, of course, favors designs that have the panels slide open - or unroll as with the international space station

    It would not be a good idea to fold and unfold the panels any more than is absolutely necessary (ie: do it only once). Even the best-designed mechanism always suffers the possibility of jamming when used in a very dusty environment -- especially if there's also a high degree of thermal cycling. From memory, at least one of the planetary probes lost the use of a camera (or was it an antenna array?) due to such jamming. To open and close the solar arrays on a regular schedule would significantly increase the probability of failure and that failure would likely be catastrophic to the mission.

    I don't understand how people are complaining about how the batteries are slowly decaying or that the solar day length is decreasing with the onset of winter. If it even takes three days to recharge in the winter - and you can only do 1/2 the work in a regular day: you'd still have a working probe as opposed to not having a working probe. If it can survive long enough, you'd get around to summer again

    I suspect that the extremely low temperatures encountered on Mars would fatally damage the battery packs if they weren't kept warm. Once the amount of energy available during the martian winter day falls below the level required to maintain the battery temperature overnight -- the cells would be irreversibly damaged.

    My Li-Ion cell phone battery has been discharged and recharged hundreds of times over the course of four years - and it still holds a usable charge. I thought that airgel was supposed to solve the temperature problem for the electronics (they can easily build spacecraft where the internal temperature of the electronics is maintained at whatever you want)

    There is no such thing as "perfect" insulation so energy has to be expended overnight to keep the critical components (batteries, etc) from being damaged by freezing. As mentioned above, once the energy extracted during the daytime becomes insufficient to provide this heat -- the mission is over.
  • by Iron Sun ( 227218 ) on Tuesday March 09, 2004 @04:35AM (#8507865)

    I'm hoping the next rover (or the next one to built) will sport some elegant new hack suggested by some Jane Average.

    The next planned Mars rover is the Mars Science Laboratory [space.com] to be launched in 2009. It will be five times larger than the current rovers and will be powered by a plutonium RTG, giving it at least a year, probably more, of operation. Check out the link for details on its proposed landing method. Very cool.

  • by pe1rxq ( 141710 ) on Tuesday March 09, 2004 @05:38AM (#8508033) Homepage Journal
    'reversing the polarity' usually only works in Star Trek :)

    The problem with such measures is that you will need some kind of special coating on top of the panels (either anti-static, or conducting to hold the charge) and that is going to result in less efficient panels.

    Jeroen
  • Re:Conversions... (Score:2, Informative)

    by Anonymous Coward on Tuesday March 09, 2004 @05:51AM (#8508070)
    > an error converting from the English system to the Metric system

    A small point, but you mean the Imperial system (which was used by the US). England uses the Metric system for almost everything. (Transport law is still mostly in miles-per-hour though)
  • by Cee ( 22717 ) on Tuesday March 09, 2004 @05:57AM (#8508084)
    I still don't know why it is so hard for some people to make links out of URLs. Anyway, here's something to click on:

    Link [cnn.com].
  • by herrison ( 635331 ) on Tuesday March 09, 2004 @08:44AM (#8508613) Homepage
    Last night, the Royal Society [royalsoc.ac.uk] webcast an interview with Pillinger. It's due to be available [royalsoc.ac.uk] on demand soon. In answer to the many points about 'reinventing the wheel', it's claimed (about 3/4 the way in) that ESA weren't allowed access to Nasa airbag technology.
  • by mikerich ( 120257 ) on Tuesday March 09, 2004 @09:26AM (#8508839)
    how does that mean they had no idea the air was so thin?

    As Mars Express closed in on the planet, astronomers noticed a large dust storm building on the planet. Martian storms are unusual in that they markedly heat the atmosphere. As dust particles are swept up into the air, they absorb solar radiation and radiate heat - warming the atmosphere, increasing the force of the wind and so raising more dust. As the air warms, it expands and pressure drops.

    All three landers were committed to landing on Mars at a particular time from the moment they blasted off. Unlike Viking, which could sit in orbit and wait for ideal conditions, they had to land directly. The two NASA landers had a larger safety margin and made it to the surface, Beagle 2 had almost none and may simply have landed too fast.

    Unfortunately having a stand-off orbiter is expensive in terms of weight and neither the Delta IV nor the Soyuz/Fregat could have sent a useful orbiter and a lander to Mars. The alternative would have been to use the much bigger Titan IV or Proton rockets.

    And this isn't the first time a Mars lander has been affected by adverse weather, the Soviet Union's Mars 3 became the first craft to land on Mars in 1971. It touched down in the midst of a dust storm and returned data for only 20 seconds before mysteriously falling silent. The Soviets believed that its antenna had been knocked out of alignment by the storms.

    Best wishes,
    Mike.

  • by Mr2cents ( 323101 ) on Tuesday March 09, 2004 @01:03PM (#8510677)
    Sorry, I meant for future missions. Maybe the next rover will have a mini-rover driving over the solar panels of his host..

I have hardly ever known a mathematician who was capable of reasoning. -- Plato

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