Simulations May Explain Loss of Beagle 2 Mars Probe 98
chrb writes "Researchers at Queensland University have used computer simulations to calculate that the loss of the US$80 million British Beagle 2 Mars probe was due to a bad choice of spin rate during atmospheric entry, resulting in the craft burning up within seconds. The chosen spin rate was calculated by using a bridging function to estimate the transitional forces between the upper and lower atmosphere, while the new research relies on simulation models. Beagle 2 team leader Professor Colin Pillinger has responded saying that the figures are far from conclusive, while another chief Beagle engineer has said 'We still think we got it right.'"
Re:How weird (Score:5, Insightful)
another chief Beagle engineer has said 'We still think we got it right.'
They got it right, yet the mission failed. What sort of weird mental block do these people have?
Something else might have gone wrong even tho the choice of spin rate was the correct one.
Re:How weird (Score:5, Insightful)
Re:How weird (Score:4, Informative)
well according to the current score, the game is about a 20 all tie -- although this doesn't count any points scored this year
http://www.bio.aps.anl.gov/~dgore/fun/PSL/marsscorecard.html [anl.gov]
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Yes it is:
Mars Express fired its main thrusters on December 25 and successfully entered Mars orbit. The Beagle 2 lander, however, has not been heard from.
And why shouldn't the Mars Global Surveyor be counted as a success? The site looks accurate to me.
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Re:How weird (Score:5, Funny)
In Doctor's terms: The operation was a success, but the patient died.
Re:How weird (Score:5, Insightful)
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What I'm wondering is why they only send out one probe. Why not two or three and have some kind of redundancy? For something so mission critical, well... you'd think they would have more than one of them up there.
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Those things are a bit expensive, so rather than have 3 of those probes burn up one after the other due to a design fault or cosmic rays; they send one, check the results, and only *then* think about sending another.
Re:How weird (Score:4, Insightful)
If the spin rates were off afterall, then they could have lost two or three probes instead of one. It's always a gamble, and if a mistake with big consequences has been made, sending more probes might not give you more chance of success...
Re:How weird (Score:4, Informative)
For something so mission critical, well... you'd think they would have more than one of them up there.
Beagle 2 was not mission critical - it was an underfunded bolt-on to Mars Express, which is doing quite nicely, thank you.
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The Brits made the same mistake the Soviets kept making: making the probe too complicated before you have experience landing. They should have made Beager lighter and simpler for the budget they had. Maybe some cameras and ONE good soil experiment.
Some of the Soviet Mars landers had a little rover on a tether. It was a clever idea, but too much for a first mission. (It could be argued that the Vikings were too bold also. But th
I hate to break it to you, but... (Score:4, Insightful)
but that's not how it works in grown-up land.
...slashdot's not grown-up land.
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Knowing even just a small bit about how people can behave, explain to me how this is "weird".
Something or other went wrong, and they're all defensive about it. Sounds normal to me.
Re:How weird (Score:4, Funny)
Are you talking to me?
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I've worked with people like this. Most engineers are 25% about themselves and 75% about the task when they're working, and regress to 50%/50% when playing with gadgets at home or showing off their phones in the pub.
The likes of Pillinger are never less than 50% about themselves, no matter how urgent a crisis is or how obviously wrong they are.
They always screw up, but they've worked so hard to bolster their image and gain crdibility among their peers that, at least in their own world, they never really fee
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It's no different than the "dark matter/energy" concept of
"Damn, your calculations are totally wrong, and your model is a piece of shit."
"Nooo... The universe lies to us! There is some dark stuff that we can't see, or measure, or anything ever, that has just the effect to fix our model, and nothing else!"
"How convenient!"
It's fine, there's no evidence somethings off... (Score:2)
It's only a flesh wound!
from expensive fireworks department (Score:2)
this could have been cool to watch. poof, nothing.
Oh sure. (Score:1)
Hah! They're just trying to hide the fact... (Score:4, Funny)
.... that The Transformers got it.
They where told to report it as a complete loss (Score:3, Funny)
Re:Come on, it's british (Score:4, Funny)
Name a one thing British ever made right.
Canada.
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Cider
Come on, Cider... (Score:3, Informative)
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Rugby, Football.
Fixed it for you.
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A billion Indians disagree.
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A billion Indians disagree.
About what? That the poms are okay at rugby and football, or bad at Cricket? C'mon it can't be the cricket.
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Cricket was something good that the English invented.
I think we can agree that the English cricket team is another story.
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Pomp and circumstance
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Dji Ingliti langwij and haw it iz speld.
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Name a one thing british ever made right.
Beer.
Re:Come on, it's british (Score:5, Informative)
Name a one thing british ever made right.
Railways. Television. Electric motor. Flushing toilet. Steam engine & locomotive. Computer. Seed drill. Tank. Custard. Cat flap. Jet engine. World wide web. Penicillin.
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Some of these had minor British contributions, but are not by any stretch of the imagination British successes in their entirety. For example, penicillin was near worthless without contributions from US scientists at Pfizer. (Fleming's contribution is vastly overrated). And lets not even start on Logie Baird.
One thing the British see
Re:Come on, it's british (Score:5, Funny)
Okay, okay. Besides railways, television, the electric motor, the flushing toilet, steam engines, computers, seed drills, tanks, custards, cat flaps, jet engines, world wide web and penicillin; what have the British ever done for us?
How could you leave off Monty Python?
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Name a one thing british ever made right.
Railways. Television. Electric motor. Flushing toilet. Steam engine & locomotive. Computer. Seed drill. Tank. Custard. Cat flap. Jet engine. World wide web. Penicillin.
Many of these are a surprise to me. I would be interested in hearing more about those contributions.
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For most of them I just looked at Wikipedia: http://en.wikipedia.org/wiki/Category:British_inventions [wikipedia.org] (most are in the English inventions subcategory).
I didn't really mean to be taken seriously, I was just replying to post that had been marked Flamebait.
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Railways. Television. Electric motor. Flushing toilet. Steam engine & locomotive. Computer. Seed drill. Tank. Custard. Cat flap. Jet engine. World wide web. Penicillin.
You forgot parliamentary democracy. And ready chopped suet.
Yes, I know the Icelandic *invented* it. The British made it *right*. Er, I meant 'parliamentary democracy', not ready chopped suet. But that was first made in Britain too: http://www.dooyoo.co.uk/food/atora-shredded-suet/1166349/ [dooyoo.co.uk]
"Gabriel Hugon watched his wife trying to f
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Name a one thing british ever made right.
Scotch Whisky.
Rolls Royce cars.
Aston Martin cars.
TVR cars.
Lotus cars.
Triumph motorbikes and cars (and bras and knickers...)
Marshall amps.
Trace Elliot amps.
Orange amps.
Vox amps, guitars and organs.
The AVOmeter.
Harrier V/STOL aircraft.
The Hillman Imp.
No, wait...
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Name a one thing british ever made right.
Australia.
HELP! (Score:2)
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Diana Rigg and Honor Blackman [wikipedia.org]
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Crazy talk (Score:3, Insightful)
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LOL, that's so BDUF [wikipedia.org], are you still in the 1980s?
The landing wasn't a failure, just the first iteration using an agile methodology. They'll get there in the next scrimmage. Or something.
Ummmmm..... (Score:3, Funny)
"Beagle 2 team leader Professor Colin Pillinger has responded saying that the figures are far from conclusive, while another chief Beagle engineer has said 'We still think we got it right.'"
-So they really *did* intend to burn the craft up on re-entry? If they did, what's all the hubbub about?
Whomever named him was pure genius! (Score:1, Offtopic)
This has to be the coolest name for a scientist I have ever encountered!:
Dr. Madhat Abdel-Jawad...Madhat FTW!!!
Or, maybe I have watched too many 1950's-1960's grade B (or some/most less than 'B') 'mad scientist' movies for my own good.
It could also be Lewis Carroll's fault for "Alice in Wonderland" having the 'MadHatter'....I just don't know anymore...
Oh yeah, have pink flamingo, will travel...BTW, WHO are you, again? [imdb.com]. (Don Ameche's character as the senile father)
Worth watching, a very funny but family safe
Explanation? (Score:4, Insightful)
There is undoubtedly something to the contention that a computer simulation does some explanatory work, but it must be in a roundabout way. Maybe this: the computer simulation provides evidence to the effect that some prior event was able to cause the known outcome; but then it is the prior event (the bad choice of spin rate in this case) that explains the loss of the Beagle 2, not the computer simulation.
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I think your idea of normal usage of "explain" may be slightly at odds with the entire rest of the English speaking world.
You seem to be thinking of the "That explains it!" context (being the explanation), rather than the "Bob explains it to Alice" (Providing the explanation) context.
I don't think you could say that one is more normal usage than the other, and I don't think anyone else had much trouble picking the correct context from the headline, even though headlines are often fairly impenetrable.
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It is nevertheless still the case that scientists tend to think these days that computer simulations do explanatory work of the other kind. It is still an interesting question: do computer simulations provide evidence at all that some events in the real world have turned out one way or another?
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Huh? The dictionary definition of explain [merriam-webster.com] pretty much matches how I've used it and seen it used all my life - and bears no relation to your "definition".
Bridging function? (Score:2)
So what is a "bridging function"? Definitely not something about Ethernet bridging... but what is it?
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So what is a "bridging function"? Definitely not something about Ethernet bridging... but what is it?
From the context, I would imagine that it is a function that interpolates between the behavior of and forces on the craft in orbit (well studied by previous orbiters) and the behavior expected in the lower atmosphere (well studied by previous probes). The intervening region is probably not that well covered by available data, so some sort of function must be guessed to fill-in the gap between the two datasets. There may be features in the upper Martian atmosphere that were not present in the bridging functi
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b = guess(a)
European Space Agency assessment found other flaws (Score:2, Informative)
ESA found many issues, mostly due to way too severe cost constraints (a "british-only" program...).
Among them IIRC, the main parachute that was changed in extremis (when the unpaid earlier maker announced they wouldn't go up to offer the flight model too) resulted in a drag coefficient t
Some Background (Score:5, Informative)
http://www.thespacereview.com/article/330/1 [thespacereview.com]
http://www.thespacereview.com/article/347/1 [thespacereview.com]
As for Colin Pillinger, note that the (initially secret) ESA report on the Beagle failure put much of the blame on project management failings and he's not been put in charge of any large project since.
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According to Wikipedia [wikipedia.org], he was diagnosed with progressive multiple sclerosis in 2005. So he might not feel up to spending the next few years fighting the inevitable political and administrative battles a project like this would involve.
Calculate This (Score:5, Insightful)
How many different independent forces could have influenced Beagle? Represent each with a variable. Calculate how many emergent properties could have influenced the craft (those arising from interactions between main variables). Assign these a variable. Estimate the range of values for each variable. Calculate the dynamics of each variable (ie. linear, logarithmic, hyperbolic, etc., including estimation of those whose behavior does not fit a simple function, instead requiring complex functions). For each variable, estimate a reasonable granularity (they may be analog, but the resulting computation would include infinities, so digitizing is necessary). Calculate the matrix necessary to represent all the possible results. Determine whether the calculations could be completed in polynomial time. Almost certainly not, so estimate how many variables (and their dynamics) must be retained and drop the rest. Calculate the solutions matrix for this reduced set. Check for polynomial time solution. If no, reduce yet again. With each reduction estimate the error range introduced, and whether any of them are unacceptable and the prior value retained.
Estimate the amount of computational power/time necessary to complete the solutions matrix, including the cost of buying/building/renting/etc. and your available resources. Calculate how many orders of magnitude there are between what's necessary to solve the problem and what you have to work with. From that estimate how much you have to reduce the solutions matrix in order to be able to arrive at some solutions, as well as how inaccurate any results will be.
Once you have the calculation of the solution set down to polynomial time and within your budget, look at how inaccurate your results will be. If the accuracy is found to be acceptable, and the calculation therefore worth doing, chances are you've made a mistake in your estimations. Almost certainly the inaccuracy will become too great before your reductions result in a solvable problem. Also note that the minimal matrix dimension will probably not be an integer. Choosing the best number of variables would be trivial, as you simply choose the next highest integer. However just because the solution here is between N and N+1 does not mean that there is only one variable with a fractional influence; estimate how many and which variables are best characterized as non-integers and select the best set of variables to use in the model. Calculate how far back into non-polynomial time your solution estimate has drifted, or at best how far over your resource budget the calculations will require.
Take a dose of analgesic of your choice sufficient to eliminate your headache. Begin building a model using the minimum number of (integer) variables necessary to arrive at a variable/value set that produces a result matching the behavior of the phenomenon you wish to model. Ignore the probability calculations that would indicate how likely it is you're wrong, and how many such wrong solutions you'll arrive at before you happen on a possibly right solution. Instead of using probability estimates to calculate statistical significance of any calculated solution, use the fact that a solution can be found that results in the same behavior as the one to be modeled, and wrongly call that accidental similarity 'practical significance'. Publish a factually unsupportable assertion that your model describes what happened based only on the fact that your model achieves the same result and count on the fact that nobody else on your research team, or anyone for that matter, is capable of accomplishing the necessary calculations described here to conclusively state you're wrong, or at best that you can't say you're right.
Estimate the positive influence the number of publications, regardless of validity, has on the probability of receiving future funding and amount thereof. Conclude that minimal-guess "modeling" provides you with the ability to say something that sounds reasonable whereas attempting to achieve real validity would take too much and too long, and that saying something is better than saying nothing, especially when the something is too hard to prove or disprove so you can't be said to have been definitely wrong.
Extra points are given if one admits the limitations of the "model" in order to state that more funding is necessary in order to determine the actual answer. The points remain good even when one concludes from all the above that arriving at "the actual answer" is probably only possible by accident, and so cannot be shown to be "the actual answer". Extra points are also given if one admits to having deleted their original response, written to take the technical details above to task, before reading all the way to the bottom and finding out that the incomputability point (and the technical validity of any or all details in the concocted example above) is secondary (though not trivial to the problems that occur when engaging in the social activity of science.
Re:Calculate This (Score:5, Informative)
The answer was 55378008.
I suspect the polarity was reversed during the process, though. You should probably view it from a vertically inverted vantage point.
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Whoever modded the parent post as "Informative" is probably to be going senile [slashdot.org]!
Whoever posted that probably doesn't have the ability to discern tongue-in-cheek moderation.
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Quite. Those who tagged this article with "moron" are the sort of invertebrates who give developers a bad name.
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Hah! You're really a climate change scientist!
The Sycorax Destroyed The Probe, no? (Score:1)
At least I thought the Sycorax destroyed it.. [wikipedia.org]
It's The Name (Score:2, Funny)
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Aliens (Score:2)
I thought it was swallowed up by the Sycorax on Christmas two years ago.
(Yes, I know that The Christmas Invasion aired three years ago, but there was that one year time loss early in the first season of Doctor Who, between Rose and Aliens of London that hasn't really been accounted for since. Should actually put Torchwood ahead a year, too.)