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Mars Rover, Spirit, Turns 4
Brandee07 writes "Designed for a 90 day mission, the Spirit Mars Rover is starting its 4th year of exploration. Spirit's sister-module, Opportunity, will turn four on Jan 25. 'We never thought we'd still be driving these robots all over Mars,' said Mark Lemmon, a planetary scientist at Texas A&M University and member of the rover science team. 'We joked about driving Opportunity into Victoria Crater, but now we're there, and we're looking at doing even more science. Each day they still work is an amazing one.'"
Title: Mars Rover, Spirit, Turns 4
Summary: ""Designed for a 90 day mission, the Spirit Mars Rover is starting its 4th year of exploration"
"Beginning 4th year" is not the same as turning 4.
You start your 2nd year of life when you turn 1.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
I've followed these things from back when they were still called Athena. Yet I still rather believed that when they said they would have a 90 day nominal mission they were purposely underselling them a little. However, when I read Steven Squyres' book Roving Mars a couple months ago and saw how much effort they put into cramming every inch of solar panels they could onto the rover because they were convinced the chances of having accumulated too much dust to continue operations after 3 months were pretty high, it was clear they were genuinely concerned about meeting their mission objectives.
In the end, of course, they landed in good weather, and much of what dust did accumulate was blown clear by dust devils. And of course, the rovers have proven to be fairly robust mechanically, as well.
NASA had clearly stated that they needed 90 days (and a few other milestones) to meet their mission objectives, but they planned from the beginning on them lasting at least a little bit longer because they put so much work into them and the 90 days was based on pessimistic dust estimates. Because of that, they budgeted an optional 90 day mission extension conditionally on them being operational at the end of the first three months. Furthermore, a second extension of 180 days was allowed if they were still in fair shape at that time (fingers crossed). But when they reached 1 year and the rovers were still going strong, they had to get special approval from Congress for funds to continue paying the operations team.
That right there tells you that no one at NASA really believed these things would last more than a year, much less four! If they did, they would have been pushing to keep their job budgeted for longer than 12 months in advance.
Bah! That's just the way space contractors avoid paying big ebay fees on the Rovers. $700 million shipping my ass.
-Dave
What have we discovered? Have we learned anything from the rock samples or pictures?
You're confusing data collection with theorizing. What we've "learned" is gigabytes of photographs, measurements, and so forth, which will, in the coming years, be used to sort through the various theories about the formation and evolution of Mars, and (more indirectly) about the possibility of life on it.
It seems likely there is something missing in your understanding of how science works, because you seem under the impression that we come up with theories and then we go do an experiment that confirms them, and if it does, that's successful science.
Doesn't work that way. What we do is go out and collect oodles of data, pretty much anything we can measure, regardless of whether or not it is relevant to anyone's pet pre-existing speculations. Then we sit down and try to explain all this data, correlate it with other data, et cetera. That's when the theories get formed, and shot down. It is, generally speaking, just a total waste of time to theorize when you have no data. That's religion, or politics, or some such non-scientific endeavor. In science we collect data first, and then we theorize, because only then can our theories acquire the solid backing of empirical fact and become actually useful. You have, in essence, imagined that the theoretical cart comes before the empirical horse.
Can you give me something that justifies all of this money spent?
Of course not. You can only do that yourself, and if you've already looked into what the rovers are doing and concluded it doesn't suit your philosophical goals, then that's that. Why would you even want a meme transplant from someone else that would make you feel differently about the money spent?
But it doesn't matter. The way it works is, we all get to decide for ourselves whether we like government money spent this way -- for whatever reason, e.g. because we think knowing how Mars formed is nifty, because we like seeing photos from the ground from Mars, because of your and NASA's 'inspiring the kids' hooey, or just because it keeps government cash from otherwise being thrown down the rathole of futile social engineering or bureaucrat full-employment programs. Then we tally up the votes. If there are more of us who think the money is well spent, it gets spent, whatever you folks on the losing side think.
As it is, those of us who like rovers poking around on Mars have more votes than those of you who don't. I can easily see why you would want to convince us that it's money wasted, so some of us might change our minds and you might become the new majority. But why would you imagine any of us in the majority would want to waste our time trying to convince you to change your mind? Who cares whether you do or not?
You're so right. I mean the $800 million spent on the rovers could have funded almost 3 entire days of the war in Iraq. And look at all of the scientific data we've gotten out of that. Right?
Coding with assembly is like playing with Legos. Coding an application in assembly is like building a car with Legos.
Spirit is in a bad way; unlike Opportunity, which has had several recent cleaning events and is still generating 650Whr/day, Spirit's solar panels have been steadily acculumulating dust ever since it left the crest of Husband Hill and descended into the dust-trap valley containing Home Plate. It's just been parked an over-wintering site right on the northern rim of Home Plate, which was picked because it allows up to a 25 degree northward tilt, turning the solar panels perpendicular to the sun and wringing every last watt from it's light. Spirit may survive the winter, but it's by no means certain. We do now know that the rovers can survive on less than half the official "rover death" power levels, because both made it through the global dust storm. Spirit's power levels should bottom out around 125Whr in (I think) about four months' time. It's going to be touch and go. With luck we may get another two earth years from her. Oppy, on the other hand, is still going strong. If some major mechanical failure turned it into a stationary weather-station vehicle, rather like Viking, it could conceivably last another five years - until the batteries finally lose capacity.
"None are more hopelessly enslaved than those who falsely believe they are free." -- Goethe
In 4 years, Spirit has driven a total of 4.6 miles, while Opportunity has gone 7.2 miles.
On Apollo 17, two astronauts on a manned rover went 12.5 miles, in a single drive, in a single day.
When they came back to Earth, they brought 243 pounds of rock and soil from the lunar surface along with them.
Spirit and Opportunity are a phenomenal achievement, and the men and women who created them should be justifiably proud of all they've accomplished. But it's sobering to realize that much of what the rovers have done in the past four years could be accomplished by humans in a few hours.