...not only do I still find it amazing that the little fellas are still up there mucking around on Mars... but I find it extremely cute. I personify everything, so I see Disney plots in my head when I think of "The Two Mars Rovers Who Could." Seriously. It's a great accomplishment and has helped so much with research. I can't wait to read about what they'll do next!!

Best luck with the dust storm guys!!

With all the budget woes the NASA has been faced with for a while now, its fantastic to see that they can still put together an impressive little piece of technology together like this.

Back in the day of the Apollo missions it seemed that no expense was spared to ensure that the US won the space race. Those were exciting times when everyone, it seemed, was behind the space program. That's definitely not the case these days. Kudos to NASA and the designers of the little rovers.

On the one hand, I'm glad that NASA has gotten so much out of the rovers ... but on the other hand I have this nagging voice in my head that keeps asking: "How can we trust these scientists to keep our astronauts safe, if they can't even figure out how long their technology is good for?" I mean, nobody seems to be focusing on the fact that NASA screwed-up royally on this one. It worked in their favour, but that doesn't change the fact that they screwed up! Clearly their calculations were way off - 3 months turns into 3 and half years? Did someone forget to carry the 1?

So NASA designs a vehicle to last 90 days and it runs for 3 years in an inhospitable environment. Why can't Ford or GM do that?

Re: Shane

Because they build them to last longer and thus they don't?

Shane, I dont think you want to pay multi-million dollars for an Explorer.. anyways I would hope not..

Either way I'd like to see Canada send out one of it's own little contraption for some galactic exploration... Or should we just hire Mario?

To mt from Ottawa, I think its safe to say that NASA made a conservative estimate when they designed the rovers. The mission had to last three months or so, therefore they had to build them to last at least that long. If they had over-estimated their durability, it would have been a colossal waste of time and resources, not to mention giving NASA another "black-eye", all of which they just cannot afford. I figure that NASA already assumed they would remain active longer than the three months they planned for, but no doubt even they are surprised they've lasted this long.

The Mars rovers were designed to run without any issues for 90 days. Any time after that is considered bonus time. As the 90 day period has come and gone, and the rovers are still running, it should be said that NASA and its crew have done nothing short of an amazing job. These two rovers are a testament to human creativity and the spirit to explore.

mt, you don't trust NASA because their machines last _longer_ than their estimates?

These are engineers. They multiply their repairs estimates by a factor of four and divide their operational lifespans by ten. That way, they maintain their reputations as miracle workers.

It is amazing that the rovers have continued this long, but not *that* amazing once they got through the initial few weeks. Some things to keep in mind:

- The 90 day period was the 'warranty' period once the rovers were off the landers and wheels dirty. Many of the most critical events that happened before this point had to go right just to get the rovers on the ground and moving around (atmospheric entry, landing, deployment, rolloff, etc.). Once they're rolling around, things got considerably easier and more reliable.

- Spacecraft like these are designed to have a 'graceful degradation' of their functions. Even if one of a rover's wheels is jammed (as one has been for Spirit for quite a while now), it can still move. The rock grinders for both are now totally useless. I'm sure there's more things are not quite the same anymore. The 90 day warranty was for 'full capability', not the 'take what you can get' like we have now.

- with these rovers, the life estimates were done based on some environmental estimates that were 'conservative', especially with regard to dust buildup on the solar panels. There's been generally more power available than anyone thought, and the power situation we're seeing with the dust storms was expected earlier on in the mission.

That said, the engineering and operations teams have pulled these little machines through some pretty tenuous situations, so all the kudos go out to them!

While I love to follow the stories of the wonderful technology that achieves such incredible feats. However, why are we North Americans spending so much on space research and not spending anywhere near enough money on R & D to develop Hydrogen powered vehicles and the infrastructure to refuel them continent wide. Surely it is more important to figure out how to do away with fossil fuels and turn to an environmentally friendly fuel that produces no pollution and can be made from water. Love the techno stuff, but let's get our priorities right.

Hi Martin,

I agree we need to place higher priority on reducing fossil fuel usage. The fact that you mention H2 as the replacement - and not battery electric vehicles - illustrates just how far we have to go to get the wider public informed and on-board. In short, we have the technology and have had it for quite some time, but this is a Mars Rover story, so back to that...

Carl Sagan was the ultimate spokesman on space research and defender of its funding. Yet, he was the first scientist to alert the rest of us to the dangers of global warming. What do we make of this? Answer: He understood that consciousness-raising and increasing the general public's understanding of science, the Cosmos, and our place within it is the key to better policy. That, and the fact that as a society we are capable of parallel processing - carrying out many simultaneous threads of learning and development. Oftentimes, R&D breakthroughs in one area contribute to advancements in a seemingly un-related discipline. We understand global warming issues far better than we would have otherwise had it not been for earlier space expenditures.

You're right to point out, as Sagan himself would have done, that it's all pointless if we lose our biosphere to global warming or nuclear war. Let us champion this important area of humanity's understanding of the Cosmos while also getting the word out that battery-powered electric cars and plug-in hybrids are the key to our survival - not the H2 system that will require 5 miracles to happen in order to be viable. (ref: "Who Killed The Electric Car? documentary narrated by Martin Sheen.)

One other point for mt (and others) to note about spacecraft lifetimes: this isn't the first time that a mission has gone on long beyond its original publicly stated mission time. The original Voyager mission specs called for an exploration of Jupiter and Saturn, because that's all the budget there was. The design engineers knew full well that extending the mission to Uranus and Neptune was an achievable goal, even if the people with the purse strings didn't want to listen to such grand ideas. So they designed the spacecraft and the mission so that a fully functional spacecraft was hurtling towards Uranus at the end of the original mission, and the budget was miraculously found. I'm sure the Mars rovers were designed with same Spirit, and looking for the same Opportunity.