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Mars Rovers Alive Until 2005?
maggeth writes "The BBC is reporting that negotiations are under way to extending funding for the Mars rovers beyond this September. Originally designed to work for 90 Martian days, they now predict they may last well beyond the 250 Martian days they had announced previously." hoferbr writes "A new analysis by Phil Berardelli at the United Press International quotes Steve Squyres, chief scientist for the Mars rover mission, in which he says that the Mars rovers '... could go into 2005'. Spirit and Opportunity will complete six months on the Martian surface on July."
This is great news. Not only for the science, but it also adds to NASA's credibility. Sure, they thought it would only last 250 Martian days, but when it comes to funding in the future, this may help, however little.
WWJD.... for a Klondike bar?
A Martian day is not much longer than an Earth day - 24 hours, 37 minutes as opposed to 23h, 56m.
The Raven
I read that last line as " Spirit and Opportunity will compete six months on the Martian surface on July."
I hope they do. Might as well go out with a bang after such success. Might be a way to get funding too.
Go here for teh [sic] funny.
Just one extra mechanical arm with a small wisk broom to brush dust off the solar panels, and those rovers might last for a decade.
I'm glad that NASA and JPL have had such a great success with the two rovers. Maybe the amazing results of this will inspire manpower and funding for future missions.
Unmanned robotic missions are great for doing science work, and they should definately continue without scaling back funds. However, it is equally important to continue working on human space flight simply to prove that we can do it and to prepare for the time when a human colony on the moon or mars is paved by the groundwork of unmanned missions.
If anything it'll give us some good data on what Martian conditions do to hardware in the long term.
I know that right now one of Spirits wheel motors was starting to act up a bit.
As Martian "Winter" approaches, it'll be interesting to see what really cold weather does to the rovers (other than breaking them).
However, with that all said, I think we should be vigorously working on putting a colony on the Moon.
Yes Francis, the world has gone crazy.
Or conservative estimates. I've had hard drives rated for around 3000 hours that lasted more like 60000.
Starbucks have just opened on Mars and the helpful staff have offered to clean the rover's solar panels once a day and stick in a couple of extra AA batteries.
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
But for 900 million bucks, you'd expect they could do just a little better than 90 days :). In all seriousness, though, good news for NASA, and it might raise morale in the organization while they try to re-organize to become a bit more effective. Re-orgs always hurt morale - at least they're standing a little higher when they take the hit.
:).
This is the first of many such outstanding successes, I hope
-Erwos
Plausible conjecture should not be misrepresented as proof positive.
That is good engineering!
:-)
Kodos to the designers !
Ditto on that. I've long complained that they didn't use an RTG or SRG on the craft. It seems that the engineers did such a good job that it was unnecessary.
I *still* think that probes should use RTGs, though, so that we can get the best bang for our buck.
Javascript + Nintendo DSi = DSiCade
In other news, NASA plans on visiting all 3,158 Starbucks locations on Mars.
It would be cool if it didn't suck.
Kodos to the designers !
Kang to everyone else !
LaForge: "Yeah, well I told the captain I'd have this analysis done in an hour."
Scott: "How long would it really take?"
LaForge: "An hour!"
Scott: "Oh, you didn't tell him how long it would *really* take, did you?"
LaForge: "Well of course I did."
Scott: "Oh, laddie, you've got a lot to learn if you want people to think of you as a miracle worker!"
-- "Relics", Stardate 46125.3
...the second they release Mars Rover: Longhorn.
Having spent $X billion so far, (and worth it, imho), the worst blunder possible is to deny the additional funding. Now that the probes are up and operating, a dollar spent here is worth ten (if not more) spent tomorrow, because the risk phase is over. Everything we get now is bonus.
<semi-sarcasm>Anyway, most of our politicking seems to be based on "not telegraphing weakness"... So, don't cut short the mission, or else the terrorists win.</semi-sarcasm>
"A witty saying proves nothing." ~Voltaire
"d'Oh!" ~Homer
I destroy stickers trying to peel them off. Imaging a robotic arm doing the same. It would be more retarded-looking than those Skill Crane games at the bowling alley trying to pick stuff up.
It would be cool if it didn't suck.
This is another example of NASA doing the technical stuff right (rovers that can last much longer than the original project speicifications required), but bad budgeting. They pay huge amounts to build the rovers and rocket them to Mars, but then they have to negotiate whether they can fund continuing to use them once they're already there?
The real headline here is "NASA considers turning off working rovers because they project budget was exeeded."
His website offers insight into why he does this ('to be different') and has pictures of the 4000+ craters he's visited.
"Is this just useless, or is it expensive as well?"
On Earth, the mean solar day is (almost, but not quite exactly) 24 hours.
The Earth sidereal day is 23:56:04.
A Martian sol is a Martian solar day.
The hardware may work or may fail, workarounds for errors may be found or not, things may be fixed, with cautious use the rovers may last for years...
Until a storm comes.
Martian dust storms come with wind at 200km/h or faster, carrying sand and smaller rocks, picking anything that isn't attached to the ground and carrying it for hours. One storm, and the rover is past, pieces of it scattered over several thousands of kilometers. And a storm will come sooner or later.
That's why there was a design of "tumbleweed" style rovers: they never deflate the airbags and let the storm carry them, letting them travel for half the planet in random direction, gathering data, until the storm weakens and leaves the "tumbleweed" in place until the next storm comes.
Current design... may live until 2005 or longer... if the storm doesn't come.
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
I don't think the analogy quite fits. Even if they are over-engineered, the extra rover lifetime isn't wasted as the hypothetical bridge's load-bearing capacity would be. Their extra life is probably even more valueable when you factor in the realities of how infrequently we have the opportunity (mod me down for the pun, i'll burn the karma) to conduct this sort of research. Unless we run out of rocks to look at and gullies to traverse, let the rovers operate as long as they are able to return useful data.
Bush Lies On the Record.
The parent refers to the length of an Earth day when the planet's rotation is measured against the "fixed" stars (sidereal time). More precisely, this "sidereal day" is 23 hours 56 minutes 4.091 seconds. Measured against the sun, however, the length of an Earth day is 24 hours. When you use the fixed stars as a frame of reference, the motion of the entire solar system puts a little extra "English" on the spin of the Earth.
Not if you are still within your budget...
In addition, like most engineering projects, you have *minimum* requirements, and that is what you build for. A bridge in the US by code MUST be designed to hold 6 times (iirc) the maximum weight it is designed to carry- in the case of a bridge, this would mean 6 tractor trailers filled to the brim w/ heavy cargo stacked six high. In Nasa's case, I am sure all the components have a mean time before failure calculated, and then probabilities are calculated as to how long it will last. So lets say they built the thing and took on a 10% chance of failure before the mission's intended end ( which I believe was 90 days). So now they are seeing that the components are more rugged than they estimated for, and will last longer. I dont see this as bad.
Im sure this is not entirely by chance- I am sure the Nasa leaders understand that headlines like "Mars rovers may last over a year past their 3 month intended life" go over much better than "Mars rovers fall short of intended year mission" regardless of the actual length or ambitiousness of the mission.
I really hope you are not in the bridge building business...
But the real logic is along those lines. NASA doesn't want to over promise, that will lead to trouble for them. If they say they'll get six months out of a device and it dies of normal wear and tear after 3, well then people are going to want to know who fucked up.
I'm sure NASA figured that, to a high degree of certianty, the rovers could pull 90 days no problem. So you report that as the expected life. If they last longer, great, but if they don't no one is going to bitch. Given the big unknowns of a mission like this, you want your estimate to be nice and conservative.
Also, you want to priortise your research. If you put a 90 day cap, you make sure to priortise the most important stuff to happen in that window. Then you can move on to other stuff, even if that's not the most efficient way of doing it. Even if you have to sacrafice some efficency, yuo don't want to do low priority stuff first because that's more efficient, only to find that your hardware broke so you never get to do the high priority stuff.
Having spent $X billion so far,...
The total cost of the Mars rovers (combined) was $820 million, including operations for the first 90 days. The extended mission - another 150 days - was budgeted at $15 million.
"Not to be too trollish, but if you are building a bridge to hold 10 tons and it ends up holding 100 tons, you are wasting resources."
As if your mama reads those signs before she crosses.
"Derp de derp."
So the OP was correct, for X == 0.82.
That puts the 300 meg one at ~12 years old, and the 1.6 gig one at ~9 years old. Both drives are never turned off.
.. onto current media. ;)
High chance, then, that when you finally do turn it off, they won't come back up. I get a lot of clients that say their ancient servers worked great for a decade and then after a power outage *boom* nothing. Make a backup while it's still running
All NASA needs to do is find some evidence of materials that could be used in the manufacture of weapons of mass destruction and we'll have Rovers all over the red planet.
Of course the new Rovers will be contracted out to the biggest campaign contributors and NASA will quickly be integrated into the Department of Homeland Security and tasked with finding fossil fuels throughout our solar system...
ANWR, hell! We got Jupiter!
I ferment meat and I'll have the food groups wired...
They were bad estimages, they were safe estimates. They designed the rovers to be tough enough that they would work for 3 months even under the worst situations (Like a bad landing, or bad dust storms and the like) So when none of these potentially bad things happen, the life expectancy of the rovers increases. Its like cancelling a cable substription and having them not disable your account for a month afterwards. You planned on having it terminated at the end of the month, but as a bonus you got free cable for a month.
As far as the rover's longevity, it's a simple matter of underpromise and overdeliver. This is typical behavior of anybody setting performance review goals and objectives. It's also done by middle managers when they discuss departmental goals with upper management.
Self awareness - try it!
The longer mission means they can accomplish everything they'd hoped to, not just everything they needed to. This means there's less of a case for "We need to send another rover to do more of this" in the future, so either another mission may not be needed or a future mission will not need to waste resources (especially weight, in space exploration mass is money) duplicating the instrumentation and capabilities of these rovers.
Also, since we know the rover design appears robust and successful, it could potentially be reused for another mission without designing a new rover. Let's send one to somewhere like Europa. That'd probably require a larger solar panel or some other power source but the rest of the design could be kept the same, saving the R&D budget.
If we're actually going to do a manned mission to mars, it's also a good idea to test our electronics and mechanical engineering for the environment BEFORE the people get there and depend on it to breathe, so better we learn how to build reliably for mars now.
Introducing the new Occam Fusion! Now with sqrt(-1) fewer blades!
This has been debated a few times here at slashdot. I learned everything I needed to know from the following NASA report:
PDF file here
High chance, then, that when you finally do turn it off, they won't come back up. I get a lot of clients that say their ancient servers worked great for a decade and then after a power outage *boom* nothing. Make a backup while it's still running .. onto current media. ;)
:-)
What happens is that the heads collect a lot of gunk that's normally scrapped off when the heads park. If they don't park enough, they can end up "sticking" to the parking spot. Oddly enough, I haven't run into that problem yet. The machine has been turned off a few times over the years (primarily power failures before I got a UPS) and I've never run into this problem. Gotta love quality parts!
Javascript + Nintendo DSi = DSiCade
One of the team leads called Cartalk a few weeks ago. They asked about building something to clean off dust, and he said they get asked that ALL THE TIME. They looked at a variety of solutions, from windshield-wipers to peel-off stuff to blowing compressed air across it.
In the end, all of the solutions weighed more than just making the photocells 50% bigger to allow for dust build-up, so they did that. They were very tight on launch space and weight.
The reliability of a complex system made of thousands of parts depends on statistics, whereas the reliability of a bridge depends on much simpler stress calculations.
If you design a complex system such that there is very little chance that any one of its components will fail within 90 days, then each component must be individually designed to last much longer than 90 days. The center of each component's reliability bell curve must be well beyond 90 days so that the product of the tails at the 90 day mark is acceptably low. The system as a whole will therefore probably last much longer than 90 days. If it does, that's not necessarily a sign of overdesign.
If the design life is 90 days, and you design for 115, and you miss miss and only get 60, the project fails in many of its requirements. And it's not like you can go to the corner store and get a replacement part. This isnt like a light bulb, where if your 2000 hour bulbs last an average of 2005 hours, you are ok.. even if some of 'em only last 800 hours. This ONE has to last at least 90 days. Period. If your mandate is to guarantee a very high probability of a 90 day life, it isnt at all unreasonable that if things dont go wrong, you can get 4-5 times that.
The thing is, NASA really needs the rovers as long as possible, so NASA engineers them the best it can with the resources we give it.
Then, when it comes time for NASA to apply for a budget to run the rovers, the agency gives a conservative estimate on the rovers' lifespan. It gives an estimate they are confident they can deliver on.
This accomplishes two things: First, it keeps the budget request relatively low, which makes it more likely that the budget request will be approved. Since there's no mission at all without the budget approval, it makes sense to give a conservative cost estimate and a low budget number.
Second, it makes it easy for NASA to deliver on what it promises. If NASA announced that the rovers could last as long as six months or more, and one of them broke early on, NASA would get no credit for making it as far as it did. Rather, you and thousands of other asshats like you--including several asshats who have some direct authority over NASA's budget--would excoriate the agency for falling short of its goals.
Better to engineer the best rover you can with the resources you have, and give a conservative estimate of the mission's lifespan. If it exceeds that estimate, bonus! NASA goes back to the budget authorities with a clear win under their belt, another project delivered as promised, and some solid results to show that an addtional budget allocation is justified to continue the mission past the lower time limit and towards the upper end of the lifespan estimate.
What's more, by doing the budget approvals in stages like this, it gives you and I (and the budget authorities, of course) an opportunity to judge the value of the first 90 days before committing 250 days' worth of budget to the mission.
And the best you can come up with is "those NASA assholes must have been padding their engineering estimates! Unacceptable!"
Another thing: You don't win any credits by quoting "scotty" in "tng". Consider this: NASA is a government agency. It has to deal with politics, bureaucracy, and the human error that attends on every complex undertaking since the dawn of time. You yourself can't spell, punctuate or use basic grammar with any consistency. Yet you presume to criticize the methods NASA must use to achieve great feats of engineering and exploration. What is wrong with you?
Any sufficiently well-organized community is indistinguishable from Government.
Think about it: when NASA says they expect a rover to last for (say) 90 days, they don't know that for sure. They can make an educated guess, but it's based on a whole bunch of uncertainties: the chance a major component will fail, the weather on Mars, the specific nature of the mission once they see what's around, you name it. So, really, when they say it will last for 90 days, they mean there is a 99% chance it will last at least 90 days ... but that also means there is a 99.9% chance it will last 60 days, and a 50% chance it will last at least 200 days.
I'm making those numbers up, of course, but that's the basic process. In statistical terms, the lifetime of the rover is a random variable whose distribution NASA estimates before launch. Because mission failure is such a disaster (you can't repair the rover!), NASA has to define mission success as something they have a good chance (say, 99% or better) of achieving. That means that the stated duration of the mission is the 1% quantile of the lifetime distribution of the rover (still with me?). That's a pretty small quantile -- by definition, there's a 99% chance the rover will last longer than that, and a very good chance it will last much longer.
So, we shouldn't be surprised the rovers have lasted as well as they have, and we shouldn't accuse NASA of being overly conservative. They're being exactly as conservative as they need to be to have a good chance of mission success.