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Simulations May Explain Loss of Beagle 2 Mars Probe
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.'"
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.
this could have been cool to watch. poof, nothing.
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In Doctor's terms: The operation was a success, but the patient died.
Sleep your way to a whiter smile...date a dentist!
Yes, perplexingly, there exists the possibility that they selected the correct entry spin rate but the mission failed for another reason. It's one of those perverse physics concepts like things falling down and cats and dogs not living together. Frankly, if it turns out that their own spin-rate calculations were valid and correctly computed, yet they caused the mission to fail, we'll have learned something very important for future missions. They could just throw their hands up and say "yes, our spin rate calculations were guff" to satisfy you that they do not have a "weird mental block" but that's not how it works in grown-up land.
No kidding!!! What do you say at this point?
Furthermore, their choice of spin-rate may have been made with the best possible available knowledge and approximation, and still been fatal. In which case we will have learned something - perhaps something really important, given how many Mars missions go awry - about successfully landing probes on planets.
No kidding!!! What do you say at this point?
Everyone always blames the bridging function...
.... that The Transformers got it.
In fact, it broadcast 13 seconds of footage. It can be viewed here. http://au.youtube.com/watch?v=wFvUdt9BQhU
This space for rent
Name a one thing British ever made right.
Canada.
Now, this may be crazy talk, but shouldn't you do the computer simulations BEFORE sending the $80m craft on it's way?
...Had this been an actual emergency, we would have fled in terror, and you would not have been informed.
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.
Cider
"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?
Knowing Google's lust for data collection, the Soviet Union is still alive and well inside the psyche of Sergey Brin....
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
There is something wrong but interesting about the idea that a computer simulation can explain what happened in a real-life incident. In the normal usage of "explain", only causally-related events can explain other events.
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.
Pomp and circumstance
Come on, Cider is french :-D
Herve S.
The second world war.
http://michaelsmith.id.au
Are you talking to me?
At the bottom of the
Rugby, Football.
Fixed it for you.
http://michaelsmith.id.au
So what is a "bridging function"? Definitely not something about Ethernet bridging... but what is it?
Colorless green Cthulhu waits dreaming furiously.
Dji Ingliti langwij and haw it iz speld.
At the bottom of the
There has been a very detailed assessment of this failure by the European Space Agency at the time, and the guys were quite competent being the ones that built the (successful) Huygens probe to Titan embarked on Cassini.
:(
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 that was smaller than the drag of the front shield, this big "bottom" device that you drop immediately after the peak entry aerothermal flux. Having such a drag ratio means the front shield could perfectly have slammed back onto the descent module upon release, or just inside the parachute itself with the consequence you can imagine (all of this happens at around Mach 1).
And that one was just an issue among others...
I'm searching for that ESA document but I just can't track it back right now
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.
Random Thoughts From A Diseased Mind (Not For Dummies)
Name a one thing british ever made right.
Beer.
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.
http://www.thespacereview.com/article/330/1
http://www.thespacereview.com/article/347/1
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.
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.
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...
Squirrel!
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 seem to be inventing very well though is SURVEILLANCE SOCIETY.
They also invented Pop/American/etc Idol too. Something someone should be nuked for.
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...
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.
Best troll for a long time, but I cannot resist biting ... how about Monty Python?
A billion Indians disagree.
Remember, it takes 42 muscles to frown and only 4 to pull the trigger of a sniper rifle.
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
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
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.
http://michaelsmith.id.au
At least I thought the Sycorax destroyed it..
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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 feel the failure at all.
Name a one thing british ever made right.
Australia.
Cricket was something good that the English invented.
I think we can agree that the English cricket team is another story.
Remember, it takes 42 muscles to frown and only 4 to pull the trigger of a sniper rifle.
but that's not how it works in grown-up land.
...slashdot's not grown-up land.
This is clearly a matter of an unfortunate choice of names. Naming it "beagle" was clearly asking it to wander off and get lost. Any beagle owner will be able to attest to this.
British you see, useless. If I had a Luger, eh? Think of it, scientists properly equipped. The answer's with you, the voters.
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!"
Any sufficiently advanced intelligence is indistinguishable from stupidity.
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?
Well, thanks to the Internet, I'm now bored with sex.
Diana Rigg and Honor Blackman
What?
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 they were well-funded and well-tested and fricken expensive as a result.)
Table-ized A.I.
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.
For most of them I just looked at Wikipedia: http://en.wikipedia.org/wiki/Category:British_inventions (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.
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.)
#include <signature.h>
That has some odd things. For instance, MGS is counted as a success. Also, Beagle is not mentioned anywhere. I don't think that "score-card" can be considered very accurate.
He only asked for one thing, gosh!
Sig: I stole this sig.
It's only a flesh wound!
It is no longer uncommon to be uncommon.
America? ;)
We all know the Martians shot it down. They're just trying to cover the facts up.
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.
They hate being called martians. Their proper name is the Zhti Ti Kofft. http://www.uncoveror.com/zhtitikofft.htm http://www.uncoveror.com/icegeysers.htm
The Uncoveror: It's the real news.
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/
"Gabriel Hugon watched his wife trying to finely chop a large piece of suet and thought that he may make many housewives lives easier by selling ready chopped suet. He sold his engraving business and in 1893 he opened The Atora Suet factory in Openshaw, Manchester."
Christmas puddings have never been the same -- thankfully.
DNA is a Turing machine. You, however, being dynamic and emergent, are not.