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The Rovers That Just Won't Quit
smooth wombat writes "Like the Energizer bunny, the two martian rovers just won't quit. Spirit, after climbing to the top of Husband Hill during the past year, spent two months examining rocks at the top of the hill and scientists confirmed that those rocks were similar to rocks found along the side of the hill indicating that Husband Hill is probably the result of an impact crater.
It will take about two months for Spirit to make its way down the hill after which the next target will be a feature called Home Plate located about a half mile away.
Opportunity is exploring the northern rim of Erebus Crater, the largest crater between already-explored Endurance Crater and its next destination, Victoria Crater.
The rovers were only supposed to last three months but have been operating for almost two years. NASA has also released a 360 degree panorama of images taken by Spirit as it explored Gustav Crater."
Maybe..
For two reasons:
1. It raises the expectations for the duration of unmanned missions. If future missions don't last as long people will obviously compare it to these.
2. Funding. If the perception is these craft last a long time then maybe people will say you don't need as many.
I wonder if there are any realistic estimates on how long it will take to properly digest the data that has been sent back by these robots. The original estimate was for the rovers to survive 90 days and they figured that the data received would occupy planteary scientists for years to come. The data they have now ought to occupy scientists for decades.
Oh, that's right... NASA's main purpose isn't exploration or science, it's to preserve its own existence. New projects mean new money, and old sucesses are only good for arguing for more funding for new toys.
Erik
to the guys responsible for the whole mission, from cleaners to engineers to management. Surpassing a mission duration by at least 700% (*knock on wood*) is a nice change from all the missions Mars has claimed so far.
The grass is always greener on the other side of the light cone.
The problem is, when you build them less robust, they might not survive the landing, so you would get a zero livespan...
Sure, so next time they build an unmanned probe without so much redundancy and resiliency, and something small breaks on the thing rendering the entire craft useless. You don't think they would get heat for that?
Space flight is hard. Landing on another planet is hard. Driving around on another planet by remote control is hard. The redundancy and robustness is built in to these systems because we know there are about 10,000 things that could go wrong, and we want to protect against these things. If we don't protect against these things, and one of them happens, we can't just call for a tow from the MAA (Martian Automobile Association).
Rover's Daily Schedule
Thats a problem with your mind, not with NASA's strategy. In short, the actual construction costs of the rovers are a very small portion of the cost of a mission of this nature. Skimping on the construction isn't going to save significantly on design costs, nor is it going to reduce the cost of flinging it halfway across the solar system and monitoring it on the way.
What you call "Over-engineering" likely only increased to cost of the project by a couple of percent at most, and greatly improved the chances of success, avoiding the necessity of paying all of the overhead costs _again_ to lauch another one because this one plowed into the ground.
Penny wise, pound foolish as my Grandma would say. :)
Why?
These things are horribly over-engineered. Not that it is a bad thing they are proving so resilliant, but we're now at 8x the "designed" life span. In my mind, that means they could have probably built it half as robust and still been outstanding pieces of machinery(and alot less expensive).
:-)
If I may interject, WHO says they're overengineered? In fact, to the best of my knowledge they are anything *but* overengineered. When the Spirit rover had technical difficulties shortly after landing, one of the things that came out was the lack of backup systems and the inability of the craft to keep its solar panels clean. Things that many of us wished the rovers had were RTGs, Solar Panel Wipers, Longer Lasting Batteries, Redundant Computers, Larger Storage Capacity, Anything but Vx[Doesn't]Works, etc. NASA hadn't put many of these goodies onboard because the rovers were built in a relative hurry, with all expectations of short lifespans.
Unexpectedly, it turned out that pretty much all the components on the rovers far exceeded their expected lifetimes. As far as the engineers are concerned, the solar panels should be caked, the batteries shouldn't hold a charge, the wheels should be gunked up, and the computers should have no remaining capacity. Yet the rovers live on. Very puzzling for the engineers, but very nice for the scientists.
Javascript + Nintendo DSi = DSiCade
This sort of space exploration is realively cheap, considering the payoffs involved. I suggest we knock off a couple "bridges to nowhere" from our budget, or ask for some money back from the Big Dig, instead.
The expense is getting them there and the teams monitoring them. The cost of the robot is trivial, hence the over-engineering.
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Finding that the same stuff is seen across a modest locality is important, since it rules out explanations that would produce those things in only very small areas.
I expected the same when I was 12 and we had just landed on the moon.
Now, at 48, I'm not so sure.
Things have changed quite a bit from landing.
In Opportunity's case you land in a 5ft deep crater, then you drive to one that is 40ft deep and find out that you have 40ft of rock, instead of the 5 you only new about for sure before. That is huge, it tells you a lot about the time and amount of water and other materials involved. So checking that those rocks were all largely the same for almost a year in Endurance was a big deal. And as Steve Squyres recently noted in his update "blog" on Cornell's website the blueberries have largely disappeared where Opportunity is now. They don't know why but the going theory is that they have encountered yet another new rock strata they had not previously seen, they started to look for a good exposure to investigate a few days ago. Soon you'll be approaching Victoria crater, and you'll get to find out if you have hundreds of feet of sulfates, which would imply possibly millions of years of the presence of water at the location.
Spirit has seen several VERY interesting rocks that are sulfates as well as layered bedrock. To say that the same slightly basaltic rocks are all it has seen is an innacurate statement, although the vast amount of material in gusev appears to be basaltic in origin.
If you're a US taxpayer, you spent the price of a few cups of milky coffee. I absolutely got value for my money. The pictures and stories are awesome. Perhaps there will be some valuable science coming out of this too; time will tell.
There are also many intangible benefits. This is the kind of stuff that makes kids want to be engineers, reminds scientists why they do research instead of working for a bank, and makes bright people from around the world want to take their skills to the US where they could maybe make robots that go to Mars!
Unfortunately that last one has been made a little tricky when NASA is forced by the government to stop hiring foreigners after 9/11. It's tough on JPL managers when they can't hire a brilliant Australian or Japanese engineer because some Saudis declare war on the US.
In summary: way to go, NASA. Some things you get right, and the robot Mars missions are incredible. But since it's my latte money you're spending, I could use a little less Space Shuttle and I'd prefer you were able to hire the best engineers in the world, no matter where they come from.