Mars Rovers Celebrate Their 1000th Sol On Mars

Cherita Chen writes, "Yesterday NASA, Cornell University, and the USGS celebrated the Mars Exploration Rovers' 1000th Sol on the Red Planet. The first rover to land, Spirit, reached the 1000 Sol mark a few weeks ago while the planet was in Solar conjunction. 'Opportunity,' Spirit's twin, and the second lander to make the bounce to Mars, celebrated the milestone yesterday while sitting atop Victoria Crater on the other side of Mars. Both Rovers are still operational (though Spirit is limping) and are sending back valuable data. Not bad for what was slated to be a '90 Sol' mission."

Comments

Come On.

[Anonymous Coward]

Admit it, you're getting misty.

Congrads NASA!

[edwardpickman]

Biggest success since the Moon landing. It proves NASA can still excell they just need to dump some baggage like the shuttle and get back to what they do best, space exploration. I'd love to see them release a disk of all the Mars images. I'd pay good money for a full set of images especially if they included a set of the aerial shots. It could help open up the research to people that don't have direct access. A lot of things have been found just from Google earth. I'd really love to see a similar thing done with all the mars images. I know it's been started but there's a massive number of images availible. Better to have a few million eyes searching them than a few hundred.

Re:Congrads NASA!

[jkerman]

the nasa HiRSE team is releasing full resolution images from the new orbiter as they are processed. its fantastic! their site seems to be down at the moment but it has the pictures, and a sofar interesting blog from some of the image processing team http://hiroc.lpl.arizona.edu/

Usual x10 engineering factor

[RichMan]

Can we say it is due to the usual x10 engineering safety margin?

90 sol * 10 -> 900. Sort of close to 1000%.

The engineers would have looked at MTBF (mean time between failures) of the components and probably designed for at least a 99% survivability to 90 sol. This might factor down to a 90% survivability to 900 sol depending on the failure curves for the parts. So the the probability of two surviving that long would be 0.9 * 0.9 = 0.81 or 81% chance.

Re:Usual x10 engineering factor

[imsabbel]

Spacecraft dont use x10 engineering safty margins.
They dont even use 50% margines.

If they did, they would never be able to lift of the ground.

Re:Usual x10 engineering factor

[Vellmont]

Can we say it is due to the usual x10 engineering safety margin?

I don't know. How many other rovers have been deployed in the Martian environment that we can get data back from to determine component lifetimes? I only know of one, and it was a much smaller rover.

I find it pretty amazing that these machines have worked as long as they have. I can't imagine it's an easy job to design a rover to last as long as it has without really being able to test the thing in the environment it's going to be in. Sure you can simulate parts of the environment, but I doubt you can simulate them all at the same time with all the parts working together.

Many people seem to pooh-pooh the survivability of these things because they just assume they were over-engineered. I'm sure they were over-engineered, but the amazing thing is that they were over-engineered in the right way, and pretty cheaply too (820 million to get them to Mars and the first 90 days of operation).

WTF is a Sol?

[Palshife]

From TFA, "A sol is a Martian day, which lasts 24 hours, 39 minutes, 35 seconds."

Sol2k "bug"

[QuantumFTL]

I've mentioned this on /. before. I used to work on MER (one of the devs of Science Activity Planner/Maestro, as featured on /.), and while lasting longer than 90 sols was not considered completely ridiculous, lasting over 1000 sols (with both rovers!!!) definitely was. Our directory structure contained a 3-digit sol number, and a lot of calculations were carried out using only the first 999 sols, including some code I wrote (knowing this to be the case).

Luckily the Operational Softare System team had plenty of time to work this issue, and it even fascilitated the introduction of newer, more capable software into the mission, as if we were already changing everything, why not ad some great stuff. I wish everyone on MER great success with the next 1000 sols!

Re:Silly Jargon

[exp(pi*sqrt(163))]

I just hope they never have probes on Mars and Venus at the same time because calling both types of day 'sol' will be confusing (though admittedly Venus is a little different). The length of the Martian day is a property of Mars, not of the Sun. It should have a name that reflects it's Martianness.

Re:Silly Jargon

[exp(pi*sqrt(163))]

You mean like:

using namespace Mars {
        "On the fifth day of their missions the Shock and Awe probes on Mars are doing fine. Shock is current exploring the northern polar cap and Awe is..."
}

using namespace Venus {
        "As we approach half way through Harsh Questioning's first day on Venus it has just circled successfully around a pool of molten lead..."
}

Yeah, that might work.