NASA Extends Rover Occupation of Mars

iocat writes "Reuters reporting that NASA is extending the Rover missions on Mars by another five months. However, they point out that while the rovers look poised to greatly exceed their planned life cycle, they could basically die at any time. Still, it will be cool to see a little more exploration."

Comments

Almost first post

[Pi_0's don't shower]

I wonder how much terrain these rovers can explore in 5 months, or if they're basically useless because of range limitations?

Re:Almost first post

[Jott42]

If memory serves me, they have a range of 30-75 meters /day, after the recent sofware upgrade. Which would give a maximum distance of over 11km, given that they dont find anything interesting on they way and starts investigating it.

Re:Almost first post

[AKAImBatman]

The difficulty is in their solar panels. Eventually they collect so much dust that they don't generate enough power. Also, the rovers stay very still at night to conserve power.

Interestingly enough, the engineers nearly had an RTG working for the Rovers. Unfortunately, the outcry about Cassini pretty much killed that. It's too bad, because with an RTG, the power source would outlast the rest of the components by some 50 years!

Re:Almost first post

[Mal-2]

Even with range limitations they're hardly useless. Both rovers landed in relatively fertile areas for exploration, and Opportunity would have still been a big success even if it proved unable to leave the crater it landed in. The main thing that comes to my mind is to find the edges of the ancient ocean and explore there -- partly because tidepools on Earth are teeming with life, and partly because shallow water means fossils (if present) won't be buried very deep. I noticed very early on that the rocks Opportunity was looking at looked an awful lot like tidepool rocks, at least ones from the eastern Pacific shore (the only ones I've seen firsthand). I knew there was good reason for NASA to be REALLY damn sure before announcing there was a lot of water on Mars at one time, but I pretty well was convinced as soon as I saw those distinctive wormholed rocks.

However, it looks like their lifespan will be determined by a few factors, some of which are within human control and some which are not:

1. Dust storms. Seems to me one good one would pretty well take a rover out of service from dust buildup on the panels alone.

2. Equipment failure, particularly the "always on and draining power" type. One has already made Opportunity a little bit gimpy, but I doubt a single such failure would be fatal. Cumulatively, several would just be too much to bear.

3. Shorter and/or darker Martian days as the seasons and distance from the sun change. This won't take out a rover outright of course, but they could compound the prior two problems. At least these events are predictable.

4. The Martian Defense System finally tracks the rovers down and explodes them. Turns out the reason they didn't shoot the first time is they thought it was just another shipment of punching balloons for their nitrous oxide-fueled nightlife. Once they realize we sent ROVERS and not RAVERS, they're going to be mighty pissed off.

Mal-2

Re:Almost first post

[Sgs-Cruz]

For those who, like me, aren't astrophysicists and had to look up an RTG, it's a Radioisotope Thermoelectric Generator. Basically a nuclear power source for the rover.

Re:Almost first post

[AKAImBatman]

Keep in mind that RTGs are passive devices, not reactors. As such, the radiation dosage will never exceed that of a pound of Plutonium-238. Plutonium-238 gives off a significant amount of radiation (half life of 87 years), but it's all Alpha particles. Since the Pu-238 is emitting Alpha particles, the radiation tends not to even make it through a piece of paper, much less the indestructible casing they pack these things in. Besides, the heat generated by the Alpha particles is what gives the RTG power. Doesn't make a whole lot of sense to let your power escape. :-)

I'm still waiting for the first mission where they use SRGs (Stirling Radioisotope Generators). Those little stirling engines are far more efficient than the heat differential of RTGs. If the tech works out, it could even be a boon for lower powered devices on Earth. I figure that a tiny SRG with about 5-10 grams of Pu-238 or Sr-90 could power your cell phone for 50 years. A laptop (depending on the design) could be powered by 100-600 grams.

It's NOT "occupation".

[Dark Lord Seth]

It's "liberation" instead, people.

Re:It's NOT "occupation".

[Anonymous Coward]

Not Troll, +1 Funny.

Especially funny when you consider that the Martian Defences were reallllllly good at taking out bogies until NASA pulled an unprecedented 3 for 3, 100% success on their landers.

Continue the liberation of Mars! Soon it will look just like Earth, scattered bits and pieces of long-range weapo^Wmetal everywhere.

All we need is some smog and we can call it home!

Occupation?

[pldms]

It's an occupation of Mars now? I thought the were just tourists.

Hope they didn't skimp on construction.

[PIPBoy3000]

"However, while Spirit is past its 'warranty', we look forward to continued discoveries by both rovers in the months ahead."

Maybe they should have gotten that rust-proof coating after all.

Wow

[Auckerman]

Who would have thought they would extend it again this soon after extending it the first time?

Excellent!

[qualico]

Its always good for future missions if the current ones exceed expectations.

Looking at Mars, now a distant orange glow in the sky, it amazes me that we have intelligence there.

Good job NASA.

NASA Press release 4/8

[morcheeba]

This was posted on JPL's rover site on Thursday. It's got a lot more info.

Re:Why? Because it is inexpensive.

[David Hume]

Why? Did they decide to extend the mission because people love following it and want to keep it going? Or are they extending it because they haven't found anything "big" to report on yet?

I expect at least part of the reason is because it is inexpensive. According to the Reuters report, "NASA said it would spend $15 million more to keep the rivers exploring the planet's surface through September." Can you think of a more cost-effective way for NASA to spend that money?

Let's hear it again for JPL

[Steve the Rocket Sci]

Pasadena's Jet Propulsion Laboratory (JPL) has done it again, it would seem. When the Voyager 1 and 2 missions were launched in 1977, they estimated that they would only last until the encounter with Saturn roughly four years later. Now, in 2004, they are still returning useful data, at a distance of over 90 AU from the Sun (in comparison, Pluto is only 40 AU from it). Sure, they had their problems during the mission, but it looks like Spirit and Opportunity may share a similar quality construction. It's definite that they won't last 27 years, but with how well they are functioning, I think the only limit will be the Martian dust collecting on their solar panels. When they Next Generation Rover lands on Mars in the latter part of this decade, it will hopefully use nuclear power, and overcome this obstacle.

Re:unmanned missions

[morcheeba]

I hate to argue with your logic, but here goes:

Robots can run basically forever, until something breaks or they run out of juice.
Somehow running out of this consumable is better than a human running out of their consumables (food and air)? If you want to be accurate, there are mechanisms for both to regenerate these consumables -- solar cells and plants.

One unique thing about people (besides their intelligence) is their self-healing characteristics ... if a robot gets a little hole in a hydraulic tube, it'll leak until it's empty. A human would clot that blood and carry on. If a human breaks a leg, you can bet they'd figure out a way to complete the mission with just one leg... I wouldn't give a robot those odds, even if they lost only one of six legs.

But, I agree.. unmanned missions are great, just for totally different reasons: low cost and hence, the ability to many missions to many different areas, each with new instruments designed to test theorys proposed by the results of previous missions. A human mission would blow the whole budget with just one trip.

Re:unmanned missions

[anzha]

If these things prove 1/50 as durable as Galileo did

If I may extract something I read from a post on Usenet a few years ago by a real astronomer (Frank Crary) about Galileo:

JPL and NASA say that Galileo accomplished 80% of its science goals, and they got that number (as I understand it) by going through the list of science goals, giving each a yes/no value, and dividing the number of yes's by the number of items. Usually, it isn't that simple. There is, ``yes, but not as well as we wanted'',``definitely yes, but we could have done better'', ``no but we still got some good data along those lines'', etc. Nor were all the goals of equal value, although you could argue endlessly about which were worth more than others. Then you get into the never-never land of things that were not on that list. I'm fairly sure that magnetometer data on the existence of an ocean on Europa wasn't on the list, and I'm quite sure that similar data on an ocean within Callisto definitely wasn't (just to use one example I'm familiar with.) Often, when you observe something, you discover something you did not expect to find. In several cases, Galileo has done that. Would there have been more unexpected discoveries if the high gain antenna had opened? Yes, definitely. But how many and how important? How can you attach a number to something like that? I would say that Galileo is a success, but not a complete success, and that the sum total of the scientific results is between 50 and 100% of what it might have achieved. I don't know, and I don't even know how to figure out, where between 50 and 100% the ``real'' value is.

That's from here.

Two notes.

First being that Galileo didn't provide more science than we hoped for. In many ways, it provided a lot less than we hoped for. I'm not calling it a failure, BTW.

Secondly, be careful whatcha say online...it might come back to haunt ya years down the line. ;)

Software Issues

[QuantumFTL]

All the scientists here at JPL are very happy to see that we'll be getting more science, however one of the issues is that we're going to be moving to a less efficient planning cycle, planning for two days per rover at a time. Also it will all be being done on earth time, which is nice for scientists, however it means things have to be planned very far in advance.

Also one of the problems we are experiencing is that a lot of the mission software was originally designed to only run at JPL on our computing environment, and is very difficult to take back to home institutions because it is so specialized.

I'm currently working on making the Science Activity Planner (the tool used by all scientists to do high level planning before they start sequencing) work collaboratively over the web. It's exciting because we're dramatically increasing the amount of people who can participate in high level planning. You can grab the public version, called Maestro, here.

One of the other challenges is the bandwidth and latency associated with transfering autogenerated data products (imagery etc) to all of our satalite institutions. I'm currently working on ways to reduce the necessary bandwidth but without lossy compression there's only so much one can do.

Anyways, this part of the mission will test out a paradigm known as "Distributed Mission Operations". You can download a paper written by my supervisor about how this was used on Pathfinder here.

Future mars missions will last far too long to bring scientists away from their home institutions and pay for temporary housing etc (which is a significant cost). Scientists want to be with their collegues and families during the long periods of exploration.

Hopefully this will prove that it is both feasible and desireable. There are several studies going on about this, but I'm not aware of any relevant links.

Cheers,
Justin Wick
Science Activity Planner Developer
Mars Exploration Rovers

Re:Software Issues

[kitzilla]

Justin, who names the rocks? You guys are clearly having too much fun in that department.

How about letting Slashdotters name one? C'mon -- nobody will notice. It's just us geeks here.

From a future JPL release:

The rover Opportunity started sol 365 this morning with a quick brush-off of the rock known as "Linux Rules." Later today, Opportunity will turn its attention to another feature, a dull-looking boulder called "SCO Drools."

Good - maybe they will run out of songs then

[Pvt_Waldo]

Personally I'm sort of tired of all the "cute" stuff. Like the wakup music and the rock names.

It's like reading a wedding announcement or something. "And the chief scientist wore a stunning black outfit, and his research maids wore matching green shirts with long sleeves rolled up. Custom pencils were used by all. The guests were delighted to see palm pilots made available for everyone, each customized with a charming orange Mars theme!"

Name a rock, 'Tux'

[Megaport]

Actually, my friend Merideth considers herself to be the feature-naming goddess for Spirit, so if /.ers will reply to this post with possible names, I'll put in one of the highest moderated ones for consideration.

Hi Justin,
How about we get the ball rolling by naming a rock 'Tux', after the Linux mascot penguin?