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Posted by: Oersted Sep 19 2010, 10:37 PM

http://en.wikipedia.org/wiki/Mars_Science_Laboratory#Power_source
"The MMRTG is designed to produce 125 watts of electrical power at the start of the mission and 100 watts after 14 years. The MSL will generate 2.5 kilowatt hours per day compared to the Mars Exploration Rovers which can generate about 0.6 kilowatt hours per day. Although the primary mission is planned to last about 2 Earth years, the MMRTG will have a minimum lifetime of 14 years."

I know it might be considered hubris, but I cannot get this number out of my mind. If all goes well after landing, we might have a mission that will outlive some of us Earthbound followers. With JPL famously over-engineering the rovers, I am convinced that they have done something similar for Curiosity. Are there any mission-critical components that - with 100 percent certainty - will not last beyond two-three years? I doubt it, but would like to know.

If all goes well on landing, and if the rover longevity is what we might hope, what will that mean for how we approach this mission conceptually? - Obviously no "living-on Mars-time" as in the early rover days. Probably no mad dashes, thinking that every day could be the last. But will we ever really see MSL being operated with a long-term plan in which a grand research design spanning several years is being adhered to? Would that even make sense?

Your thoughts please...

Posted by: djellison Sep 20 2010, 12:10 AM

If we had known Spirit and Opportunity would last years - would their first 90 sols have been any different?

Maybe - slightly. They might have taken more time in Eagle crater, perhaps. BUT - you CAN NOT run a mission with a primary mission of 2 years, under the assumption you will last 3, or 5 , or 11. Those two years you run the rover as hard as you can, get the most you can out of it. Then and only then as you approach the possibility of an extended mission do you start thinking about how to run beyond that. The engineering and science teams will begin to shrink, the abilities of the rover diminish. It's a moving goal.

Posted by: SFJCody Sep 20 2010, 01:44 AM

I think it's possible that if Curiosity is successful, and at least one of the two MERs is alive at the time she lands, then January 3rd 2004 will become known as the last date in human history that there were no working assets on the surface of another world.

Posted by: Oersted Sep 21 2010, 02:20 PM

Cody, I do hope you are right! That is an amazing thought...

Doug, if Curiosity is doing perfectly well one year into the mission, I think it would be natural to start entertaining thoughts of more elaborate planning for an extended mission. Budgetting needs to be in place, choices made about destinations, etc, etc.

Say, if Curiosity is at a "bifurcation" of routes one year into the mission. One route leads to a short-term interesting place that could be fully explored in a year. The other route leads towards a much more target-rich environment, but one that would require a year of travel to get there. What would the mission planners choose?

- It is a tough one. And I'm sure somebody will start thinking hard about it the moment MSL is on the surface if not before.

What would you (UMSF member...) do in a situation as that described above?

Posted by: djellison Sep 21 2010, 03:01 PM

Speak to headquarters.

Posted by: Oersted Sep 21 2010, 03:47 PM

so that would be: speak to ..... you?

Posted by: djellison Sep 21 2010, 04:08 PM

No, NASA HQ.

You will see mention of having to march up the chain of command when making decisions such as entering Endurance, setting off for Victoria etc.

I don't see much value in a discussion that's guesswork based on forecasts based on assumptions, all of which are probably based on misconceptions.

Posted by: pospa Dec 6 2012, 09:25 PM

Curiosity mission extension, ... already?

From space.com http://www.space.com/18769-mars-rover-curiosity-mission-extension.html?goback=%2Egde_2003867_member_193185821 :
Curiosity's mission was originally planned to last two years. It has now been extended indefinitely.
"We've already decided with this plan that we will continue to operate Curiosity as long as it's scientifically viable," John Grunsfled, NASA's associate administrator for science, said here Tuesday at the annual fall meeting of the American Geophysical Union. "And that could be a long time."
...
"I never get a straight answer on this, but I think it has 55 years of positive power margin," Grunsfeld said.

Posted by: stewjack Dec 7 2012, 12:47 AM

Hmm There is this place just to the north of Gale Crater. It's called the Lowlands. Might be an interesting place to visit.

Posted by: Explorer1 Dec 7 2012, 01:44 AM

Ha, on that timescale, and if nothing happens to the wheels, a visit to Spirit might be in order; Curiosity may outlast this forum, actually.
2067 here we come!

Posted by: Fran Ontanaya Dec 7 2012, 02:05 AM

Maybe this frees right away the next rover from carrying some redundant instruments, i.e., there's less pressure to bring another meteo station if MSL's is going to be active and budgeted.

Posted by: ToSeek Dec 10 2012, 05:24 PM

Curiosity is the first time I've thought that a space mission might well outlast me.

Posted by: MrNatural Dec 11 2012, 02:28 AM

Let's not get too carried away; MSL does have finite limits on instruments and resources. The ChemMin specification (D. Blake et al) notes: "During the nominal MSL mission of one Mars year, the ChemMin CCD will be damaged by high-energy neutrons from the nuclear power source..." so performance will degrade after that (although steps to ameliorate this have been taken). There are a bunch of other limits, some more serious than others. Off the top of my head here are few: There is a limit to the amount of helium carrier gas MSL carries. Residue may accumulate in the quartz cups but that may not be a problem. And there is a limited supply of solvents in the wet cells limiting the amount of polar (i.e. amino acids) chemical extractions that can be done.

Hopefully MSL will last long enough to come up against these limits for even if it is half-blind (as Opportunity is now) with a degraded ChemMin CCD and depleted wet cells etc., it is still an incredible machine. I sure hope the MSL nominal mission of one Martian year is as accurate as the 3-month estimated lifespan of the MERs. JPL has an excellent track record so I am very hopeful.

As far as Mt. Sharp, Matthew Golombek noted in an excellent pre-landing briefing that MSL will not travel above the sulfate layers because it is thought that area is dominated by soft aeolian deposits.

Posted by: nprev Dec 11 2012, 03:21 AM

The longevity of MSL is subject to a large number of random factors which will only multiply as the spacecraft ages. We can't know what will happen.

Let's just be grateful for each & every sol.

Posted by: PDP8E Dec 12 2012, 01:32 AM

There has already been a decade long process of funding, designing, instrumenting, building, and delivering MSL to Mars. There are thousands of very smart scientists, engineers, technicians, principal instrument investigator teams, and the leadership team working this 2 billion dollar mobile laboratory. This 'super team' (and future funding) will take MSL (and us!!) as far as she can go... I prefer to trust the operational decisions of the team that we entrusted with MSL

Absolute best case: twenty years from now (~2033) MSL has long since been a primarily stationary observation platform delivering long term weather data, radio science, and seasonal surveillance images until the the RTG falls below positive power (2050?-2060?) - think Voyager.

Who knows... some future NASA/JPL/MSSS programmers (being born today) may design and upload a novel OS to do incredible things...

But, as we all know, a few critical failures can shut-down MSL at any time. To paraphrase Nprev and others: each Sol, image, data return, and discovery is a gift.

So, buckle up and enjoy, this may be a long ride!

... updated my bucket list: #39 Outlive MSL (in 2053 I will be 100 - yikes!)