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Mars Lander goes Spelunking!
Khan writes "Seems like the Polar Lander may have landed a little too far..about 1 mile deeper than expected into a canyon and probably broke apart in the process. Check out the article in the Miami Herald." According to the official Mars Polar web site, they are still looking for it, or at least some evidence of a crash. Maybe some Martian dragged it to its garage for spare parts.
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You know, we can screw up a lot of robotic missions, leave a ton of craters on Mars, and still get the scientific data we want for much less than sending a manned mission to Mars.
A manned mission would cost several orders of magintude more than a fleet of simple robots. We'd have to provide a human-liveable habitat for astronauts that was absolutely fail-safe, to prevent loss of life (and the loss of a far more costly mission). We coudln't do a "fast-better-cheaper" human mission. The risks are too high. And risky missions are what steered NASA away from the huge, monolithic "everything including the kitchen sink" mode of exploration. I'm not talking about just the risk to human life, but the risk of failure of the mission.
And yes, I've heard the "but astronauts are brave pioneers who know the risks" argument. Even if we find people to shoot into space on a risky mission, I'd rather not spend a huge amount of money so some rocket jocky can Evil-Knevil his way to Mars.
We still know very little about Mars. Mars is a more complex evironment than the moon, and a hell of a lot further away. While manned missions to Mars will make sense someday, now is not that time. I'd say, let NASA continue with its plans. The funding we're expending on these missions isn't so great that screwing up and losing a few robots is such an issue. The more we learn about Mars in this "little to lose" mode, the safer (and probably more cost-effective) any future manned exploration will be.
Gee if it is that hard to land remotely, perhaps we need to admit that one of the only sure ways to avoid this kind of disaster in the future is to let a human pilot control the craft in real time...by being there!
Neil Armstrong saved the first moon landing by flying the LEM over a giant boulder (which a robot lander would have hit) because he could make decisions based on the immediate circumstances. If it is still too costly to send people, perhaps we need better computers - AI systems which could simulate the emergency decision making processes of a crack pilot like Armstrong.
Until that time, expect a lot more of these failures...small, cheap and fast just doesn't seem to be doing what NASA thought it could.
BTW, I'm more inclined to believe in "other" reasons for the failure of this and other Mars missions (at least 2 previous US missions and 2 previous Soviet missions). Kinda makes you wonder...
Never by hatred has hatred been appeased, only by kindness - the Buddha
Cruise stage separation failure explains what we've seen. The DS2 probes, intended to impact and penetrate the surface, also failed to communicate to Mars Orbiter. What could cause both the Lander and both DS2s to fail?
After the last communication with the craft, it was supposed to rotate for reentry, and the cruise stage (carrying the interplanetary solar array and thrusters) would separate from the Lander. The DS2 probes were on the cruise stage.
If the cruise stage did not separate, the DS2 probes and the Lander were destroyed. Single point of failure, whatever the reason for the failure. It explains why the Lander and the two DS2 probes failed.
What I want to know is this: having designed and built a Mars probe, what's the marginal cost of building another one?
And if that cost is low, why not launch two missions; one shuttle mission to put 10-15 identical probes into a stable Earth orbit (hang 'em off the side of the Space Station even!), and one ELV (expendable launch vehicle) to put a bus with a big dumb tank of fuel and rocket engine into orbit a few days/weeks later?
The shuttle's reliable - it's manned, it's going into orbit, and it's coming back after it deploys its payload. The space station will be reliable; it's manned, it's not gonna fall down. So the odds that your science payload (the Mars probes) will be lost before launch are pretty slim.
The big dumb tank of fuel with the rocket engine on the back is expendable - it can be "as reliable as the rocket used to launch it", that is, "pretty good, but if it fails to reach orbit, we launch another one, our science payload is still safe".
The next step is pretty obvious - strap the bundle of probes onto the big dumb tank and fire it off, using whatever gravitational slingshots you like.
10 probes en route to Mars for the price of one expensive shuttle launch and one cheap ELV boost to low-earth orbit is gonna be cheap.
As a bonus, you get some statistics on lander reliability. Was Pathfinder "lucky" and Mars Polar Lander "unlucky"? Find out when you do the same thing next year with 10 MPL-style landers. "Of 10 MPL-style landers, only 3 made it. Of the 7 failed MPL landers, 6 of their DS2-style probes survived and transmitted; the bug is probably with the lander itself, not the separation of the probes. We were just really unlucky with the 1999 MPL. Of the 10 airbag-bouncy-landers, 8 survived. This is the better technology to use."
$150M per mission is faster/better/cheaper than $1B per mission. But $400M for 10 missions beats both hands down. We know re-entry is difficult - we don't know how hard "separating probes from busses is", but it seems pretty simple a'la Galileo. (And with 10 probes in my hypothetical mission, if one gets "stuck" on the bus, big deal, there are 9 more where it came from :-)
(FWIW, here's my guess as to what happened to MPL: Since the DS2 probes also failed to respond, I really question the "canyon" theory - there's no evidence that anything reached the ground in one piece. Or does the "canyon" theory posit that all three (lander and both DS2 probes) all landed in the same canyon? Not having the size of the canyon handy, nor remembering the expected distance between the probes and the lander sites, I'm not sure if this is plausible or not. My gut says "there was a problem on re-entry that destroyed the probe before DS2-probe-separation" is still the simpler explanation.)
UFO spotted landing on our planet! Some scientists assume existence of terrans. Government trucks have been seen carrying something from the presumed landing site to some submartian base known as "Area 51". Government denies knowledge.
The reporters are out of their mind. This was a test flight using one of our new planes. The Planetary Aeronautics and Space Association (PASA) has carried it back to its constructors. That's all.
First post!
Guess the first one explains why it's so far off where we thought it would be.
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This story is just CYA BS.
The real answer is probably related to the rumor that NASA forgot to put heaters on the explosive bolts. This would have prevented the cruise stage from separating and the lander+DS2 probes would have burned up in the atmosphere.
Cm'on, even if the lander rolled down a ravine, the DS2 probes would still work! After all, they were designed and tested to CRASH into the surface.
Armstrong, selected for the mission because he was one of the best pilots in the military, was able to use the LEM's thrusters to fly the Eagle horizontally until he could bring it to a safe landing a few miles from the planned landing site.
Robot landers can't make on the fly decisions like that.
Had this been a manned mission to Mars, a human pilot would have been able to see that the lander was heading for a dangerous spot and, most likely, landed the craft safely.
I read an interesting book a few months ago called The Case For Mars. If you are interested in manned exploration of space beyond low Earth orbit I highly recommend it.
I used to be a very harsh critic of NASA back when the shuttle was the only thing they had flying. Most people don't realize that the reason there are six crewmembers on a shuttle mission is that until the mid-90s, all of the computer instructions were stored on punched paper tape! The "mission specialists" had the job of feeding the paper tape into the vintage 1970 computer while the Flying Winnebago did laps around the Earth for a week.
Each shuttle mission costs more than the $165MM we paid for the lost Mars lander. The way I look at it, compared to what NASA has spent in the past we should think of the Mars landers as being disposable. For about the cost of a jar of Tang and a few of those toothpaste tubes full of dehydrated ice cream, we can now send a probe to another planet. If it blows up, send another one, or two, or ten.
Sojurner was a huge success. That mission cost about $150MM. This one was a bust at $165MM. You take your chances with these things.
I think we have a much better chance of getting important science done by sending more and more of the cheaper landers. Think of them as probe droids, drop them by the dozens.
The problem is that the public's imagination is captured by manned space flight. Sending robots just doesn't do it for people the way a test pilot or scientist risking his/her life does. The sad fact is that humans are exceptionally well adapted for life on Earth and we suck at being space creatures. Our spines deteriorate, we lose muscle mass, our circadian rhythms get all fouled up. The way I see it, the only reason for manned space flight going at all right now is to give the Congress something they can relate to in hopes of keeping the budget from being slashed.
Absolutely wrong. The drive worked fine on Earth, or it would never have been flown. It apparently got a piece of debris stuck between the accelerator grids during launch, causing a short circuit, but that was cleared by pulsing current through it. After that the ion drive was a phenomenal success.
This isn't right. It's not even wrong. For one thing, none of those probes carried any solar panels; they all ran off RTG's. And their main antennas worked just fine, it was Galileo (currently sending back some of the most amazing data about Jupiter we've ever seen) which had the main antenna fail to deploy.
The solar wind does not penetrate down to the altitudes where Skylab orbited, and thus was never a factor to it. What does happen is that the solar UV increase during the height of the sunspot cycle heats and inflates the upper reaches of Earth's atmosphere, which increases air drag on low-orbiting satellites (of which Skylab was one). The Shuttle, which had been intended for use to re-boost Skylab, was delayed by budget cuts (Congress' fault, not NASA). So Skylab fell down. Not a big deal, it wasn't intended for permanent use anyway.
I'd like to see a reference for this assertion.
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Time is Nature's way of keeping everything from happening at once... the bitch.
3. JPL never said that they had the landing site pinpointed to an exact spot, and never guaranteed that the site was as flat as a billiard table.
Don't do what again? Don't send out any space probes if there is any risk of failure? Don't build any space probes until they've perfected the technology? (bit of a catch 22 there)BTW, this was one of NASA's new "low"-cost missions. According to them, the cost of two spacecraft is capped at $184M. Compare to, what was it, a billion dollars for Viking in the '70s? Given the immaturity of the technology, I think this is prudent.
Disclaimer: Currently, none of my tax dollars are paying for these particular missions. I am chipping in for the space station, however.
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Nice to see that the author went out of his/her way to mention this as "NASA's latest failure," and to remind us of the metric/English conversion problem. Funny how the complete success of the latest shuttle mission didn't get mentioned. Grrrrrrrrrrr.
Slightly disreputable, albeit gregarious
Let's put the $184 Million cost of the Mars mission into perspective. According to the Wall Steet Journal, the Air Force plans to buy 339 F-22's "over the next 16 years at an average cost of $200 million per plane" Surely a Mars mission is worth 1 F-22.
Too bad they didn't get any audio back from that microphone on the thing -- I suspect it would have picked up something along the lines of "Meep Meep!", followed by a high whistling sound and a "poof" on impact...
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Every year during my review, I just pray the words "slashdot.org" aren't mentioned.