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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."
- To the pols, NASA is a way of distributing federal pork.
- To the State Department, NASA is a way of targeting foreign aid at Russian rocket designers to keep them from selling their skills to Iraq or North Korea.
- To the career bureaucrats, NASA is a way of keeping themselves employed until retirement if they can only avoid big screwups.
- To the investigators, NASA is a way of developing new technologies and doing science. This is the only legitimate purpose of NASA, but it often gets swamped by 1-3.
When NASA is throwing away billions each year on the aging and obsolete Space Shuttle, and billions more on the station-without-a-mission ISS, it's not likely that they're going to be able to take on a manned Mars project. The pork money is already allocated and the good personnel are probably spread too thin.--
Time is Nature's way of keeping everything from happening at once... the bitch.
The shuttle seems like one of the worst places to put money. It was expensive and questionable technology even when it was originally developed. NASA (and other space agencies) have already found better ways of lifting both objects and people into orbit. Hopefully, we'll see that kind of new technology deployed soon. But then, we still have the choice of using the launch capacity for glorified space tourism (shooting senators into orbit) or actual scientific purposes (unmanned probes, space telescopes, etc.).
I can't decide which thread to put this in.
For roughly each dollar invested in NASA, 10 dollars are returned to the US economy. Actually, I think that value has increased since the eighties, but NASA has always been of benefit to the US. But because you can't SEE the results, your apparent narrow-mindedness gets the better of you, and your senators. If only my bank gave such a return for money.
The only time I wish I was a US citizen, is to support NASA with my vote.
"A goldfish was his muse, eternally amused"
Vs lbh pna ernq guvf, ybt bss abj. Tb bhgfvqr. Syl n xvgr.
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.
Both the moon and ISS have serious problems as stepping stones. The ISS is in a nice low orbit because otherwise the shuttle wouldn't be able to reach it, but ideally a set off point for solar system travel would be in a much looser orbit so that it would be easier to leave earth's orbit from it. Also it is all very well to say the ISS is useful as a stepping stone, but what would you actually do there? It could be used to assemble huge ships that were too big to be launched from earth, but quality control in an orbiting space station is going to be far worse than on the earth, and if your ship is that large then costs will be prohibitive anyway. It doesn't make a difference that you can leavefrom the ISS with very little fuel because you still need to get up there in the first place.
The moon is generally put forwar as a stepping stone because it is close to us, has a smaller greavity well than earth, and would therefore be easier to launch large ships from, the idea being that these would be constructed on the moon. The only problem is that the moon does not have an atmosphere, so you need almost as much fuel at the far end of your journey to slow down as you do at the start to speed up. Mars on the other hand has an atmosphere, and so you can use aeorbraking (orbit around the outer reaches of the atmosphere and slow yourself down with atmospheric drag). The result is that, sounterintuitively, you actually need less fuel for a trip to Mars than you do for one to the Moon. Granted the trip is longer and windwos for return less frequent which bring out other complications, but as a base for futher solar system exploration the moon is not a good idea.
The English may well beat the Americans to be the first to discover if water exists on Mars.
The Beagle 2, named after the ship used by Charles Darwin, is due to travel to Mars aboard the European Space Agency's Mars Express mission, also planned for 2003.
The 60-kg, clam-shaped probe is scheduled to land on the surface of Mars on Christmas Day 2003. It will drill into the surface to extract soil samples which will be scanned for signs of water and life.
An artists impression of the probe can be found here
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've thought for a long time, ever since NASA started this "smaller, lower cost" strategy, that they had the right idea but didn't take it far enough.
What they need is two or three rockets to go to mars and release a few dozen small communication relay satelites and several hundred (thousand?)surface probes, which can talk to any of the satelites. I'm talking about *real* redundancy, not just "let's send a backup".
As has been previously pointed out, a huge majority of the cost is in the development of the technology, not the actual construction of the equipment. So develop something that can be produced on a larger scale. Maybe half will fail, but the ones that give us information will give us lots. And we'll have the option of sending more, improved, satelites and probes that can interact with the existing ones.
And, as you make the equipment smaller you gain all kinds of advantages. What if we can send a four ounce probe that is mobile and can talk to the satelite? The task of landing a four ouncer gently is orders of magnitude easier than landing a twenty pounder gently. (I don't actually know how much that thing weighed, but you get the idea.) A look at our cell phone technology tells you these things are possible, and that's not even getting into the nano possibilites.
A three tier system might be even more advantageous: A few dozen satelites, a hundred stationary surface relays that can talk to the satelites, and 20,000 tiny surface probes that only need to talk to a surface relay yards away.
There are so many possibilities, if only they'd get a little creative. When we were all watching the exploits of the mars rover, and then it died, I thought, why didn't they just send a dozen? This seems so obvious to me that frankly I'm surprised NASA didn't go down this road years ago.
"I don't know half of you half as well as I should like, and I like less than half of you half as well as you deserve."
NASA tries to use metric when possible. The problem is that some things, like much of the aerospace industry and navigation practices, are stuck on the old units. For example, I fill my airplane with 50 gallons of avgas, set the altimeter to 29.92 inches of mercury, lift off the runway at 100 knots and climb to 10,000 feet. The whole US air traffic control system is based on English/Imperial units. How do you switch that to metric? It barely runs as it is.
On a solar-system-wide scale, the Moon and the Earth are really quite close together, so a scheme where you start at the Moon to take advantage of the lower gravity, but return to the Earth to take advantage of atmospheric braking and water landings could be the best of all worlds, pun intended.
--
Jeroen
Secure messaging: http://quickmsg.vreeken.net/
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
Well, I think eveyone has got it all bass-ackwards on this. Looking for fossilized bacteria and water on Mars? Hoping for water on the Moon? Drilling through 10km of ice to see what might live in the ocean underneath Europa's crust? If you're looking for new life and exciting, harsh environments, I'd say we look down instead of up.
Don't get me wrong - I think the space program is entirely cool. But for billions of dollars less, we could effectively conquer the ocean floor instead of trying to escape gravity and get to space.
Just think - our planet is 70% covered with water, and yet it's mostly unexplored. We still haven't explored a lot of it, and there's lots to discover. How about looking at life forms that life in 400F toxic water plumes on the ocean floor instead of looking for fosselized bacteria? How about catalogueing all the various life that we haven't yet even seen in the depths instead of searching for water on the moon?
Space is cool - it's unlimited, which gives us room for our imaginations. The oceans are at a disadvantage due to that - they're finite. But I have a feeling it would be money better spent (and less of it, at that) exploring the depths of our oceans instead of the heights of our imaginations.
Mr. Ska
When I was working for NASA at JPL in the early 1980s the decision was made to send only one Galileo spacecraft to Jupiter instead of two as JPL orignally proposed. Most engineers believed this was a mistake.
Several persons have mentioned the feet / meters error that caused the Mars spacecraft to fail. It should be noted that the error was found quickly, and, had there been a second spacecraft, there would have been time to correct it. In previous missions with dual spacecraft the two spacecraft have been timed to arrive months apart so that only one ground crew was needed for both missions (another reason why the cost is not doubled.)
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.
I'm not sure if 2 probes is really enough. They should take more of a shotgun approach, and send several hundred probes in the general direction of Mars.
Some of you might say "That'll cost too much". But if you really think about it, it'd be a way to cut costs. For one thing, if you send enough probes, the guidance systems on each individual probe don't need to be that good, only one needs to get there. The same goes for reliability and physical reliability of the system.
I guess a shotgun's not the best analogy... perhaps ejaculation's a better model; Lots of poorly designed things set out in the hopes that one works. I'm sure I could somehow equate this to Microsoft; I'll leave that as an excercise to the reader.
my sig's at the bottom of the page.
50mph, dang that seems fast. Have past (successful) landings also been that fast?
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