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Mars Crater Theory Tries To Explain Missing Beagle
JayBonci writes "CNN is running a piece regarding the failure of the Beagle Mars probe being possibly attributed to a crater landing. It's an interesting story about the variety of forensics being used to try and pick up on the lost craft."
From the article:
While they cannot make out the ship itself, the image shows a 1 km (0.62 mile) wide crater at the center of the 70 by 10 km (43.5 by 6 mile) target area near the Martian equator, Pillinger said. It is possible, although unlikely, that the Beagle may be unable to communicate because it landed in the crater, he said.
"This would be an incredibly unlucky situation," he said.
So, according to the theory, the probe didn't make a crater, it landed in one. Just to make things clear.
The Beagle 2 spacecraft was a European effort. NASA didn't build it.
On the other hand, NASA has two spacecraft on the way to Mars right now. The first one will land on January 3rd.
Cross your fingers.
This is America, damnit. Speak Spanish!
The BBC News web site has a story with a picture of the crater.
From this article:
[The crater] was only revealed by close-up pictures of the site taken by another NASA orbiter, Mars Global Surveyor, minutes after the British probe was supposed to have landed last Thursday.
"minutes after" ????
here's a mapthat shows a couple (from really far away).
Isidis Planitia is at the equator, 1/4 in from the right - there's a big crater under the "a", but you can see others...
and here's a close-up
The gray circular area on the right, in the middle, is the area in question - the crater you can see under the letter "a" in the previous map is the one that's just barely cut off on the right in this one... I think the one they think the probe is in is the one slightly north and about an inch to the west of that one.
I'm not sure when these were taken, but I was looking at them back in the spring, so they've been up for a while, i.e., not since only "minutes after" the probe disappeared...
AND, as you can see, it's very easy to tell that there are craters there - and I'm not even a scientist, nor do I have access to ALL the pix of mars...
-bs
That that is is not that that is not. That that is not is not that that is.
Its designed to correct itself if it arrives upside down (last para)
This page has several photos of the landing site, showing the weather the day of the landing (it was fine) and also the famous "crater" within the landing zone: Beagle2 landing site photos
You seem as you are really unaware so let me explain:
1. No, it won't start the experiments on it's own afaik. But it will fall into an emergency mode where it sends continously in case it's clock is broken. This might be Mars Express (the ESA-Orbiter) chance to pick up the signal and reset Beagle2.
2. Beagle was a cheapo mission therefore making it move would have cost a lot of money (even if it only was for the extraweight). It was already cheap and even if it cost millions it was very inexpensive compared to the Pathfinder or the incoming M2K4-Landers from Nasa.
3. Moving around Mars is hard, even harder when you are an autonomous robot. The biggest "moves" we made up there was the Marsrover wich was basically a small remote controlled car that went as far as 10 meters away from it's landing site (that's my assumption, not sure on the exact distance).
cu,
Lispy
The Mars Global surveyor passed over the landing site 20mins after the Beagle2 landed, the picture of the landing site is here here
I agree with your thesis, but to nitpick: you're assuming equal probability that the probe lands anywhere in the target area. If the crater is really "in the middle", that might significantly elevate the probability of hitting it. (And as long as I'm complaining, 700/(.5^2 * pi) = 892.)
Agreed on the landing bags, though.
What I'm listening to now on Pandora...
I think they can manage around 1.5 - 2 Metres per pixel, I'm not sure how big the Beagle is but I don't think it's much more than a metre diameter so it may not be big enough to show up at all.
The other alternative used in the Viking mission is to have the entire spacecraft enter orbit and then separate and de-orbit the lander. Given the entry design, I don't see any real advantage to this for Beagle. In fact, it would just add complexity in the form of additional retrorockets and propellents.
We have enough experience with direct-descent entries (all lunar returns were this way, as was Mars Pathfinder, probably others) that if the mission has suffered a catastrophic failure, it's probably not because of missing an entry corridor (which, since Mars' atmosphere is so thin, is far wider than it would be for Earth).
Bush Lies On the Record.
If you had RTFA that you linked to (thanks!), you'd have seen:
A rough landing on the sides of the crater - which could be as much as 700 metres deep - could have damaged the lander. A crater might also cast a shadow that would make it nearly impossible for Beagle to "power up" using its solar panels.
And:
Malin Space Science Systems, which operates the camera aboard Mars Global Surveyor, identified it (the crater) and sent the picture to the Beagle team late on Sunday.
Lastly, the crater walls might obstruct the line of sight to Earth at the times the lander is programmed to make attempts to establish contact.
Edith Keeler Must Die
Viking I and II lasted from 6/76 and 8/76 to 11/82 and 4/80, respectively. Depends on how long the solar cells can grab a charge and aren't covered by dust and maybe on the batteries.
Bush Lies On the Record.
A simple example--Suppose the rover had to disembark from the lander on its own, without human guidance. The lander is wedged up against a rock that wont allow the petals to fully open. Guess what. With the current design, that would have been impossible. At the end of the day, you'll have exactly the same thing you had at the start--a multi-million dollar hunk of metal wedged up against a rock with no hope of escape.
Rover? What rover?
Are you reading Mars Pathfinder pages by accident?
I could build the equivalent of those with $50 worth of parts from Ace Hardware. Why couldn't they?
Well, you'd have to test these new features. Redesign the power subsystems so they'll cope with the additional current drain (oops, the batteries need to be heavier!) Rewrite the software. Build the new hardware so it can survive the launch, six months of huge temperature fluctuations and hard vacuum, an incredibly violent reentry, being slammed into a dusty plain at tens of kilometers per hour and finally a near-vacuum with more big temperature fluctuations. And finally, make sure these additions don't weigh too much - there was a tiny mass budget for Beagle 2, and they only just made it as it was.
Easy, huh?
that isn't really the real problem on mars.
the real problem on mars is that it is somewhere between 30 light seconds (on its closest aproach) and 16+ light minutes (on its furthest) away...meaning that it is not possible to communicate in realtime with the lander. the lander is on its own, we can moniter anything it sends us, but by the time we see something go wrong it is probably too late for us to do anything about it.
I think that probes need to send more telemetry as they are in the process of landing. I think the new rovers have done this to some extent because of the Polar Lander problems.
Information here...
That would have made no difference. The critical issue with atmospheric entry is WHERE in the atmosphere it enters, this was controlled very very accurately by pointing Beagle2 before it was released by Mars Express. Once thats done Bagle simply follows newtons laws to its entry point. Beagle 2 was "spun up" before it left Mars express to stabilize its attitude so it would enter the atmosphere with the correct side down but even if this failed it wouldn't really matter all that much. Attude of Beagle on initial entry dosen't matter because as soon as it starts to hit the top of the atmosphere it will right itself so the heat shield is pointed down; the same way that a pencil dropped from a tall building will always land point down.
- "Hear that?! The percolations are imminent! Cease your ingress!"
One not so obvious fact is that the "target area" is approximately oval in shape. The landing area is pi*a*b where a and b are the major and minor radii of the oval. Thus the total area is approximately 3.141 * 35 * 22.5 = 2474 km^2.
.5^2 = .785 km^2
.785 km^2 / 2474 km^2 = .000317 or .03%
The 1km dia crater has an area of 3.141 *
So
So yeah, 2% doesn't look quite right on its face...
However, the target area is a probability distribution. The vehicle is not equally likely to touch down at all points within it. It's probably a 3-sigma target area distribution meaning you are something like 99.7% sure that the vehicle will impact within the target area, but points within 1-sigma of the target center are far more likely to be the touchdown points.
So, without knowing where the crater is in relation to the center of the touchdown spot, it is somewhat hard to say what proportion of the probability landing distribution it occupies. 2% could be an accurate probability if it is sufficiently close to the center of the target area.
Education is a better safeguard of liberty than a standing army.
Edward Everett (1794 - 1865)
What happened was twofold.
1. Food production technology continued to improve.
2. Several billion people were never born.
And what's really happening is that we're getting better at distributing and producing food faster than we are at making babies. What's more, countries like China and India that have imposed reproduction limitations are, combined with a desire to have male children, going to see their populations plummet if the measures remain effective.
Which is why I think the more effective argument isn't the population growth as much as the "all eggs in one basket" issue. Sure, the probability of getting hit by a large enough asteroid is small, but it only takes one...