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Beagle 2 Failure Theories
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."
My friends and I went to the NASA Ames Research Center Mars museum at Moffett Field yesterday and it was pretty cool, in a museum-for-kids kind of way. But there was one fact on display that I simply could not understand, and that the curator on duty could not help me with. I told my friend that I would ask Slashdot, where someone was sure to know, and was only joking, but now that this story has been posted (and although it's only loosely related), what the heck ...
The description of the rover module that is going to be deployed on one of the upcoming Mars missions states that it is designed to last for 3 months or until its solar panels become covered in Mars dust and it can no longer get the solar power that it needs. The question is, if they are going to send up a multi-multi-million dollar craft, why not put some simple wipers on the solar panels so that they can wipe off the dust and get some more use out of the thing?
The curator said that "five hundred people" before me had asked the same question, and that he had never been able to figure out the answer. And of course there MUST be a good reason for this; my closest guess is that the robot wouldn't last for more than 3 months anyway and so they don't bother to include the extra expense and complexity of a motorized wiper system just to keep its solar panels clean for longer than it is expected to live. But there must be a better reason than that, no?
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It was the Bunny Thing. Opportunity's next. Oh no!
Show me on the doll where his noodly appendage touched you.
Snoopy's Sopwith Camel doesn't look like it is set up well enough to survive re-entry.
Why don't you embrace your slashbotness instead of living in a dreamworld?
...it wasn't promised a treat or its favourite chew toy at the end of the mission.
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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.
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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
The most likely candidate as an explaination of failure is simply human error. There are rarely errors in electronics that are not caused by humans that could cause such a massive loss. Usually, errors in hardware do not exist, as the hardware is top of the line and checked and re-checked for defects. (Granted, however, that sometimes faulty hardware may slip through the cracks) It is most likely something simpler than "it landed in a crater full of quicksand and sank." However entertaining it may be to picture a multi-million dollar rover sinking into the martian soil, it simply is impossible. To create quicksand one needs water. Even though the Spirit and Opportunity rovers found evidence of water on Mars, it was a long time ago, not today, that Mars was wet. So that simply is not feasible. Space debris, while a popular theory, is so unlikely (the chances of a meteor hitting something in the middle of space are *chuckle* ASTRONOMICAL) So this leaves us with simple human error. Something as simple as a single line of code can destroy an entire project (programmers know what I'm talking about). If you will remember, a few years back NASA lost a multi-million dollar spacecraft because of an error converting from the English system to the Metric system, so it is usually something tiny like that. If you asked me, it's most likely that someone typed an extra "0" somewhere in the code for orbital data and/or surface descent for the capsule. Even though it is just one "0", over that long of a distance it would make a huge difference. Remember that each decimal place is a factor of 10! Telling a spacecraft to orbit at "100,000" miles above the surface is a whole lot different than telling the spacecraft to orbit at "1,000,000" miles above the surface. Such an error would just send the poor Beagle 2 hurtling into the vast reaches of space or crashing to the surface. So it is most likely something like this that has caused all the trouble with the Beagle 2 and given those poor Brits such a hard time.
"It may be nothing, it may be everything" said Sims. The object could be one of the explosive bolts used to secure the probe to its host during take-off. More worryingly, it could be something that broke off Beagle 2, or a wrinkle in the insulation wrapping the probe.
And on and on it goes. Kingdoms and spacecraft get lost on a dime, these days.
A wiper on the panels is like a spare wheel for a car with a bad transmission.
The dust will settle on the panels in x amount of time, but by then the batteries won't be able to recharge and there will be other mechanical problems.
I find these memes a little interesting. There's always something the 'eggheads forgot' according to the common man and its easy to believe. A related meme is how Einstein was a terrible math student when he was young. In reality, he did fine in math when he was young. I guess believing in this kind of stuff makes you feel better knowing that you're "better" than "smart people" and that life is very simple and requires simple solutions.
Then again, the conversion error from metric to imperial that caused another mars bound space-probe to fail fuels this fire, but is very much an exception and not the rule.
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.
Dialectician. Archology.
I just figured it had run off with a poodle, until I learned that there are no poodles on Mars. Then I though it landed in a puddle, until I was told there are no puddles on Mars. I guess that rules out a poodle puddle too.
Sometimes dogs just run off for no reason.
Anti-gravity? That was *my* little secret! But I never patented it! Boy, was *that* dumb!
CNN has the scoop.
--- Hindsight is 20/20, but walking backwards is not the answer.
Similar to what grand prix drivers have on their visors? If an existing appendage on the rover could hook up with a tag and pull such a layer of film off a panel then that could double the solar panels lifetime with little extra weight or complexity?
Boffoonery - downloadable Comedy Benefit for Bletchley Park
NASA's Viking Mission to Mars was composed of two spacecraft, Viking 1 and Viking 2, each consisting of an orbiter and a lander. The primary mission objectives were to obtain high resolution images of the Martian surface, characterize the structure and composition of the atmosphere and surface, and search for evidence of life.
how does that mean they had no idea the air was so thin?
every day http://en.wikipedia.org/wiki/Special:Random
http://www.cnn.com/2004/TECH/space/03/08/mars.beag le.reut/index.html
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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.
Surface pressure: 6.36 mb at mean radius (variable from 4.0 to 8.7 mb depending on season)
[6.9 mb to 9 mb (Viking 1 Lander site)]
Surface density: ~0.020 kg/m3
Scale height: 11.1 km
Total mass of atmosphere: ~2.5 x 1016 kg
Average temperature: ~210 K (-63 C)
Diurnal temperature range: 184 K to 242 K (-89 to -31 C) (Viking 1 Lander site)
Wind speeds: 2-7 m/s (summer), 5-10 m/s (fall), 17-30 m/s (dust storm) (Viking Lander sites)
Mean molecular weight: 43.34 g/mole
Atmospheric composition (by volume):
Major : Carbon Dioxide (CO2) - 95.32% ; Nitrogen (N2) - 2.7%
Argon (Ar) - 1.6%; Oxygen (O2) - 0.13%; Carbon Monoxide (CO) - 0.08%
Minor (ppm): Water (H2O) - 210; Nitrogen Oxide (NO) - 100; Neon (Ne) - 2.5;
Hydrogen-Deuterium-Oxygen (HDO) - 0.85; Krypton (Kr) - 0.3;
Xenon (Xe) - 0.08
now- from pathfinder Meteorology
It was mid-summer in the northern hemisphere of Mars when Pathfinder landed. The Pathfinder Lander is at 19.33 N, 33.55 W. The Viking 1 Lander touched down at 22 N, 50 W, 2 km below datum elevation on 20 July 1976, and is used for many of the comparisons below.
The pressures measured over the first three days average about 6.75 mb, 10% to 20% smaller than those recorded by the Viking 1 Lander during the same season 21 years ago (note that this result is consistent with the elevation difference of about 100 meters between the Mars Pathfinder and Viking 1 landing sites). The pressure showed a slight decline over the first few weeks but is now starting to rise slowly. This rise should continue through December, 1997. The pressure rise is concurrent with the slow shrinking of the southern polar cap, now at its maximum extent, as the southern winter ends.
Temperatures measured from the top of the 1 meter mast on Mars Pathfinder varied from daily highs of about 260 K (+8 F) to lows of 196 K (-107 F). This is about 10 K degrees (18 F degrees) warmer than Viking 1 Lander measurements made at 1.6 meters. The sol-to-sol temperatures have been very repeatable over the first 30 sols, and should continue until about 60 sols after landing, after which they will start to show more variation.
Preliminary wind speed estimates give late evening and early morning prevailing winds from the SSE, which shifted in the early afternoon to be from the N to NE. This is very similar to what Viking 1 found at this time of year. During the day, winds were light at only a few km or miles per hour. At night the wind speed increased to about 10 to 20 mph (16 - 32 kph) from the south.
The repeatable weather patterns of northern summer found by Viking 1 have been verified by Pathfinder so far. These include diurnal (day-night) pressure changes and semi-diurnal changes by as much as 4.5% due to atmospheric thermal tides.
Interruptions in the normal pattern of temperature drops observed on a few nights may indicate water in the atmosphere is condensing as fog. Humidity measurements are planned later in the mission.
On sol 25, temperature sampling was done at 4-second intervals for the whole day. Temperature fluctuations by 15 to 20 K (30 to 40 degrees F) were observed over minutes or seconds at some periods, suggesting turbulent boundary-layer mixing between the warmer near-surface region and cooler layers above that. A "dust devil" was also detected passing by the lander on sol 25, and later high resolution sampling has detected more dust devil signatures.
More detailed information and historical weather reports are available at the Mars Pathfinder project weather page. Raw and reduced data are available online at http://atmos.nmsu.edu/PDS/data/mpam_0001/aareadme. htm
Pathfinder used a parachute... didn't anyon notice how hard it hit? the fact that pressure and temperatures change so mu
every day http://en.wikipedia.org/wiki/Special:Random
why not stick a magnet to the bottom of the solar panels?
Both rovers carry magnets supplied by Denmark for experiments to analyze martian dust. Dust covers much of Mars' surface and hangs in the atmosphere, occasionally rising into giant dust storms. One of the magnets is designed to exclude any magnetic dust particles from landing in the center of a target area. During Spirit's time on Mars, dust has accumulated on other parts of the target while the center has remained "probably the cleanest area anywhere on the surface of the rover," said Dr. Morten Madsen, science team member from the Center for Planetary Science, Copenhagen, Denmark.
"Most, if not all of the dust particles in the martian atmosphere are magnetic," Madsen said. Another of the magnets is within reach of the rover's robotic arm. Examination of dust on the target by instruments on the end of the arm will soon yield further information about the composition of the dust, he said.
every day http://en.wikipedia.org/wiki/Special:Random
In order for NASA to understand the presentation, the ESA had to convert it to PowerPoint format.
Our spaceprogram is certainly modest compared to yours, but ESA is working hard towards some great goals in the future. Check out the ESA homepage for info on the different space science projects, such as Planck, Rosetta, Venus Express... and add to that the bold new program Aurora, which aims to put men on the moon as well as Mars. I certainly hope it will happen some day. And I also hope that ESA's budget will be greatly increased.
We can't accurately predict the atmosphere (weather) here on earth, even with dozens of satellites, hundreds of radar stations, and thousands of automated stations that monitor localized atmospheric conditions. How do you expect ESA to predict the weather on Beagle 2's landing day using 20 year old data?
If you'll remember, NASA adjusted the Rover's landing parameters immediately before landing, forcing the parachute to deploy sooner to compensate for lower atmospheric density. That very well may have saved the mission, because the chute still deployed at a lower altitude than expected.
Either Beagle 2's landing sequence was such that it could not be tweaked en route, or ESA overlooked the opportunity to make such an adjustment.
A final note. Many have suggested that spacecraft, such as the Mars Rovers, use nuclear power instead of solar power to vastly increase their operational lives. One of the main excuses I've seen to NOT use such power (besides the lobbying of tree-huggers) is to purposefully limit the mission lifetime, so resources can quickly be shifted to new science. However the 3 recent landings (Rovers and Beagle 2) have shown we do need to keep track of the weather on Mars a bit closer. If the rovers had a nuclear power source then once they broke down (as in not able to drive around or operate the arm), they could become fixed position weather stations. The data provided could aid in adjusting future landings, which could potentially save hundreds of millions of dollars.
Dan East
Better known as 318230.
if you build them they will come
(they being the windscreen washer people)
The first thing that springs to mind is that any kind of wiper wiping dust across could scratch the panels
And that was the first thing I thought of too, but then a simple rational hit me-- if you're going to end up writing off your multi-million dollar probe due to dust buildup anyway, you might as well scratch some solar panels and extend that life. Wait till it gets bad, dust, bad, dust... At that points there's no reason NOT to do it.
Weight is a legitimate issue, but then, how much could a wiper wiper assembly possibly weigh? Of course, everything had to be built to withstand the rigors of reentry, so who knows.
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