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NASA To Launch Dual Mars Probes
GoBamaRollTide points to this MSNBC article, writing: "
OK, so NASA wants to launch two identical probes, with different targets, about a week apart. Theoretically, this will allow a mission to continue, even if one has a "Major Malfunction." So, what do you think? Good Idea, or just crashing probes twice as fast? Two craters for the price of one!" Besides some interesting information about the benefits of a 2003 launch date, the article says: "Each spacecraft would be launched on a Delta 2 rocket for a 7½-month cruise to Mars. Upon entering the Martian atmosphere, a parachute would deploy to slow the spacecraft down, and then airbags would inflate to cushion the 50-mph landing."
For all of its technical wisdom, and fascination with space exploration and science fiction, I am very surprised how clueless most Slashdot folks (including the poster) are on this one.
First, NASA has sent redundant probes before. Many times. Consider : Viking 1 and 2 to Mars, Pioneer 10 and 11 and Voyager 1 and 2 to the outer solar system... the list goes on and on.
Second, the cost of the second mission is far less than the first. The bulk of the expense of a space mission is sunk into the research and development of the probe, and subsequent mission support over its lifetime... not in the material manufacture or in the launch (though these are substantial in and of themselves).
In sum, two missions can be done for less than twice the cost of one mission, and you gain enormously by redundancy. Random catastrophes are unlikely to strike both probes simultaneously, and system difficulties with the first mission can be detected and solved in the intervening time before the second probe arrives.
This makes "faster, cheaper, better" missions more feasible. These missions are being launched on mere dimes where dollars were spent before. The problem is that they have suffered from reliability issues. Two missions for the price of 1.5 missions gives one _both_ reliability and low cost.
Science, like Nature, must also be tamed, with a view turned towards its preservation.
Just from the title of this, I have to take offense.
/.'s readers would qualify for that).
> it's really dim to show bias towards someone because they have a degree
I'd say it's really dim to hire someone without a degree, at least in this field.
Sure, it's ok to hire some IT guy that doesn't have a degree but has been playing with computers all his life. I'm sure there are lots of qualified people in those fields with no degree. Besides, CS degrees are about programming, not setting up firewalls and replacing motherboards.
But we're talking about Aerospace Engineering, Physics, etc.
Here, your "screw the degree" idea fails in two ways.
First, how many people are self taught to the equivalent of a PhD level in these fields? Not very many I can assure you. At least not nearly as many who are self taught to be the equivalent of an MSCE (I'm guessing 95% of
Second, if you look at what it takes to get a PhD in one of these fields, you would realize how poorly your own experience maps onto this group of people. Getting a PhD is NOTHING like getting a BS. Most of the time spend in graduate school is spend doing research towards your thesis. Completing your thesis shows not only that you are capable of research, but you took on a long term project and were able to complete it.
Don't get me wrong, I'm not saying every PhD is good at real world problems. But if I had to choose between a PhD and someone who is "self taught", all things being equal I'd go with the PhD to design the next space shuttle, thanks.
I should probably chime in here.. We had a guy give a speech here at the U (University of Arizona, Tucson..big place for space research and all) back in 98 once all the data from the lander and the rover had been collected. This guy's job was to design and implement the cameras on both the lander (not the rover.) and clued us into the sorts of stuff they were doing with it.
Part of his speech included materials he'd brought with him from other portions of the design team. One of those things were some films of actual test-drops of the airbag system done out in the desert. Its certainly not as elegant as a parachute+retro burn landing, but it works, and works more often in tests. Simply cushioning the hell out of the unit and letting it bounce to a stop is statistically the best method to use. He pointed out an example in one of the tests where one entire side of the airbag was left intentionally uninflated -- The unit successfully bounced off the earth, settled, and deployed just fine -- It was just by luck that during the bounces, the side without the airbag was never face-down. Thats opposed to having 3 rocket burns, where 1 rocket fails.. The damn thing will cartwheel out of control and crash.
I guess it all sort of depends on how you think a landing should be done. Having it fall out of the sky on a parachute, and bounce for over half an hour (and a mile's distance!) before coming to rest can be thought of repeatedly exposing the lander to undue trauma. But it works.
PS..Seeing an ultra-high resolution slide of the surface of Mars in color-seperated 3D with a pair of 3D glasses was unbelievably cool..Handed out little cardboard glasses to everybody, and sat back for half an hour picking out things in the landscape..hehe...was unbelievably cool.
Bowie J. Poag
Bowie J. Poag
The problem is, without any resources they can't practice and improve their aim...
You need to give them enough money so they get it right first time. If the US Government wasn't taking their budget away they would probably have already put a probe on the Mars.
--- Can i borrow your Clue-Stick(tm)? I need to go beat a few people with it...
I'm starting to get my own theory's here...
According to another story I read, the missions will be webcast as much as possible.
I wonder if this means I'll have to skip watching Survivor IV to watch these rovers skitter across the surface?!
Both probes will be searching for evidence of water, but neither of them will be landed near the place where the evidence of liquid water was found recently. In the article, a scientist said that area was too rocky and hilly, and they were worried about a rover flipping over.
On the plus side, these two rovers will use airbags to bounce to a landing (like Pathfinder).
The one thing I don't get it why they launch them seperately. Why not use a single Titan IV (or equivalent capacity booster) to inject both into a trans-mars orbit? If the concern is dealing with two landings at once, just perform an orbital correction on one of them to aerobrake twice, once at a shallow angle to bleed off speed, the second one as the money shot for entry into Mars' atmosphere. The other lander could perform a standard single aerobrake and land days before the second one came in for its second encounter with the atmosphere.
The only reasons I see to using two Delta 2s are this:
1. NASA doesn't want both eggs in one launching basket.
2. NASA can more easilly get Delta 2 boosters than a bigger booster like the Titan,
or
3. NASA doesn't want to do something new like a 2 stage aerobrake.
Rich
I can't help feeling that NASA has got its priorities all mixed up.
It keeps going for all these high cost, high risk mission to far flung places on the pretext of searching for evidence of life.
As cool as this may be I think they would be better of plowing more money into a replacement for the shuttle, possibly a return to the moon, and the ISS. I know that alot of people consider the ISS a wast of money but with a bit of work it could really achieve something. All three of the above might act as stepping stones to future exploration of the solar system, providing cheaper lifting and bases from which cheaper missions can be launched.
NASA is obsessed with shooting big, dumb rockets at long distance targets at hugh cost. If only it could learn some pacience. If there is evidence of life on Mars it will still be around in fifty years time.
I think that the search for life is a laudable aim, but there are more useful things NASA could be doing with all that money, like building a platform (metaphorically speaking) from which future generations might more easily explore the solar system, rather than wasting all that time and money on short term projects for now.
NASA, and all the other space agencies, should be building the highway to the stars, not just driving to them in an offroader, year after year.
My tupence (sorry about the bad metaphor at the end)
Paul Leader