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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?
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.
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
Can that be right? 23:56 for an Earth day? Where are the extra 4 minutes? That's two hours a month of slippage--that can't be right.
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
isn't it convenient that it will work for way longer... and NASA will get more money? not to badmouth or anything, I personally think that NASA is a great agency for our country, and space is important, once we run out of resources we hopefully want to be able to go into space and get resources from other places, and NASA is definitely helping us out there, although other non government companies are doing things, space is a very expensive deal, and it is hard to do, which is why NASA needs so many resources. But it definitely would make sense if NASA underestimated purposefully just so that they could be able to impress, but that is just my opinion
You'd think they could come up with some better names for things up there in space. Patio of the Gods is pretty cool, but naming a rock afer a state? Please...
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.
You are too late. You have obviously forgotten about the little pieces of Beagle which are randomly strewn about the Martian surface.
That's why there are two rovers. Maybe one will eventually be destroyed by a storm, but both, when they're on opposite sides of the planet, is unlikely within their lifetimes.
I submitted this story last night, and it didn't get posted.
The grandparent poster was kidding, but how hard could it have been to rig a simple centrifugal pump to blow the dust off? All it takes is a simple, small, electric motor (one per panel). Perhaps they ran out of space to mount them.
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.
I'm all for using these folks as our first conscripted astronauts in such a project.
Screw that. I'm keeping the RTGs to myself. These guys don't realize that ENERGY is what keeps you ALIVE in space. (Technically here on Earth as well. We just happen to have taps on a nice Fusion generator sitting next door.) I'd send them up with a few cell phone batteries and see how long they survive on breathing lithium after they're no longer able to crack water or CO2.
Javascript + Nintendo DSi = DSiCade
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
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!
Even if Rovers are wildly succesful from a scientific point of view, sooner or later the (scientific) returns from investment are bound to decrease ; that may happen in a year or tomorrow and only the -scientist- will be able to tell us "ok, it's pointless to continue digging holes in the rocks with the current instruments".
They of course would like to dig holes with Rover forever and maybe find something unexpected : that would be nice, but maybe it would be nicer to divert resource from a project that is consistently showing diminishing new results to a new project with, maybe, more intruments or different instruments.
It's a very hard decision to take and hopefully it will based on a rational, well tought and debated argumentation ; hopefully it will not be only a decision made by people who don't appreciate the returns in knowledge.
Those, plus many other ideas were considered, and rejected. The best solution they found, as others have pointed out every time this comes up, was to simply use larger-than-needed solar panels. -that gave them the best chance of things working as long as possible. If you rely on any of these other "devices", then they become a potential weak link that could cause the entire mission to fail early.
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.
Now for the budget reason you commented on. Do you think for a minute that tax rebates of $500 to $1000 for each tax payer did not contribute heavily to the increased budget deficit? What do you get for $10 billion or more in interest over four years?
Do you wonder why you pulled out just one line of a satire to comment on?