Mars Science Laboratory

Sombebody explain this to me. MSL is a nuclear powered rover the size of a small car.
If you look at the MSL website at JPL, it staes that it will "demonstrate long-range mobility on the surface of the red planet (5-20 kilometers or about 3 to 12 miles) for the collection of more diverse samples and studies".
Why does a nuclear powered car only has 12 mile range?
Shouldn't it be able of a much much longer range?

Either they posted it wrong, or it sounds really funny, like if NASA whats to go off the record about the range capabilities of this new rover and mediatically shut it down after a while ....

Cheers

By your mentioning of nuclear power, I assume that you are thinking of nuclear fission. The MSL will use a Radioisotope Thermoelectric Generator which is a special kind of power generator, that uses the heat produced by the decay of radioactive elements on a thermocouple to generate power.

Regarding its range, take a look at the text from the official website.

The rover will carry a radioisotope power system that generates electricity from the heat of plutonium's radioactive decay. This power source gives the mission an operating lifespan on Mars' surface of a full martian year (687 Earth days) or more, while also providing significantly greater mobility and operational flexibility, enhanced science payload capability, and exploration of a much larger range of latitudes and altitudes than was possible on previous missions to Mars.

MSL website

There should be enough power to move the rover for a year, and the distance travelled would depend on the choice of the scientists, because, if they stay in a region and explore longer, the distance travelled is reduced, and if they move from one region to another fairly fast enough, they might be able to travel long enough.

that makes sense... thank you, altough in a year i suppose one can really get to know thse 13 miles prretty well :-)

So in one Martian year, it can only go 12 miles.

The isotope current might last longer than a heating to
generate current but perhaps not easily done as a thermal
battery.

An isotope current might be way more powerful than needed.

At first I thought of a base communicator that could only reach
12 miles.

reply to post by TeslaandLyne


NASA doesnt want to have a mission just to cover large distances, scientific exploration is the main goal, they may stay in a particular place for some time, if they find any interesting stuff, or else, move on to another location. So, in the end, the distance travelled will vary.

Peacejet, i agree of course , it's not a distance contest...

But You must admit that, although many sites that are in the "immaginary collective" such as Cydonia and others are probably not worth it, NASA has made some peculiar decisions on where to land their previous and future missions....

There are some incredible pictures made essentially by MRO that definetly are worth while to investigate, without necessarily landing on top of the "face"....

Some picture show things that look very much like vegetation, some others ponds with liquid water and shorelines.... With a larger range you can see more....

If you land in the sahara, you'll probably see a lot of things, but if you land in the amazon you'll see a lot more.... let's just hope we get lucky

Cheers

reply to post by shasa


There are some limitations to where anything can land, making it land on a place where the possibility of having big, sharp rocks awaiting would not be a good choice, even if it was a very interesting place.

So, until we can land something that can make long journeys on Mars we are limited to flat, smooth places, like the ones all other Mars probes have landed.

PS: I don't think that there are things that look like vegetation or ponds with liquid, but that is a different subject.

www.marsanomalyresearch.com...

www.marsanomalyresearch.com...

i'm sure this has been discussed many times.... i apologize for that.... in the second link the third and fourth picture look really interesting.... and surely look like ponds, with shorelines and rocks partially submerged.... then again, what do i know ;-)

Mod Note: Please stay on Topic – Review This Link.

[edit on Sun Apr 5 2009 by Jbird]

Correct me if I'm wrong, but the one-year mission is just the "nominal" mission. The actual length of the mission could go on much longer, just like the mission of the rovers "Spirit" and "Opportunity" have lasted over 4 years longer than the "planned" nominal mission...

And furthermore, 13 miles is an very long way to go in one Martian Year (1.9 Earth Years) -- especially when compared to the distance covered "Spirit" and "Opportunity". Even the rovers which have been going for over 2.7 Martin years (5 Earth years) and they have only gone a total of 4.75 miles (Spirit) and 9.35 miles (Opportunity).

That means those two rovers together barely covered 13 miles in the 2.7 Martian years (5 Earth years) that they have been there.

Since NASA missions often go beyond their "nominal" mission length, I wouldn't be surprised if the Mars Science Lab's mission goes longer than the planned one Martin Year.


[edit on 4/5/2009 by Soylent Green Is People]

While I am all for using nuclear energy for anything I do not see why they chose it for this rover... They could get a lot more time out of it if they installed solar like Spirit and Oportunity along with a solar panel wiper...like a window wiper. So far wind has kept the first rovers going by cleaning off the panels. Imagine if they had istalled windshield wipers

Anyway, they should use both in this rover. I mean we are spending the money to get it there it should be as technologically advanced as we can make it.

i agree, given also that this is presented as being the most expensive ( and largest ) rover we ever put on Mars....

Well, godspeed MSL !

Originally posted by Xeven
They could get a lot more time out of it if they installed solar like Spirit and Oportunity...

Solar power isn't the best method when on Mars. The Sun is further away. Dust can be a problem, even if you have wipers. It's just one more thing that can break down.

RTG's can keep the systems warm through the night and when those big dust storms happen, you don't have to worry about the lack of Sunlight. Those dust storms can last for a while too.

reply to post by Soylent Green Is People


The problem here is that, MSL is not carrying solar panels which can provide power as long as the electronics function. Instead it works on the decay of the nuclear elements, and the probe carries only a limited amount of the fuel, and once the supply ends, the systems shut down. So, working time is limited.

reply to post by peacejet

True -- but Spirit and Opportunity must be "parked" all winter and sit idle (doing next to nothing) for several months each year because there is not enough sunlight to power them during the Martian Winters.

I don't think there will be a need to park the Science Lab during the Martian winter.

I suppose they could have used solar panels to supplement the power requirements, but:
solar panels = weight; weight = money; and money is finite.

reply to post by Soylent Green Is People


True it can work through the martian winter. But consider this, parking idle for a few months and moving around for the rest of the year until the electronics wear out one day and moving through the winter but only one year. There is a huge difference, there is not much time for MSL, so whatever scientific goals have been set, they have to be achieved fast.

And they can add a solar panel, money is not a issue in case of top priority missions, but the probe must fit in the protective casing for the launch. The largest space craft, Cassini, was so huge that it needed an atlas rocket to launch it.

reply to post by peacejet

Well, I suppose one of my questions is: How time-limited will MSL REALLY be?

Is the one-martian-year timeframe the absolute limit of the RTG, or is that simply the nominal mission length? The current rovers (yes -- partially thanks to the use of solar power) have been going for 4.5 years longer than planned. Does anyone know if the RTG could possible last for several years past the "nominal mission" timeline?

reply to post by Soylent Green Is People


There is information regarding that in the MSL website which I posted in the first reply to the opening post.

This quote is from the website.

The rover will carry a radioisotope power system that generates electricity from the heat of plutonium's radioactive decay. This power source gives the mission an operating lifespan on Mars' surface of a full martian year (687 Earth days) or more, while also providing significantly greater mobility and operational flexibility, enhanced science payload capability, and exploration of a much larger range of latitudes and altitudes than was possible on previous missions to Mars.

Here is the link

The time period is just tentative. But it is highly unlikely for the fuel to last beyond two years(martian) because the amount of fuel is limited.


[edit on April 7th, 2009 by peacejet]

reply to post by peacejet


They say here that the system "optimizes power levels over a minimum lifetime of 14 years", so I guess that power is not considered a problem.

And I think that the best target would be Gale crater, not only does it look very interesting, being more than 4000 metres below the medium altitude, probably making it one of the places with higher air pressure.

But all targets are good.

Originally posted by peacejet
The time period is just tentative. But it is highly unlikely for the fuel to last beyond two years(martian) because the amount of fuel is limited.

The Viking landers both used RTG's and Viking 1 lasted for 6 years and Viking 2 for 4 years. Plus the MSL will be using the latest generation of RTG's called the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG). So it's impossible to guess how long it will last.

Originally posted by peacejet
reply to post by Soylent Green Is People

 

There is information regarding that in the MSL website which I posted in the first reply to the opening post.

This quote is from the website.

The rover will carry a radioisotope power system that generates electricity from the heat of plutonium's radioactive decay. This power source gives the mission an operating lifespan on Mars' surface of a full martian year (687 Earth days) or more, while also providing significantly greater mobility and operational flexibility, enhanced science payload capability, and exploration of a much larger range of latitudes and altitudes than was possible on previous missions to Mars.

Here is the link

The time period is just tentative. But it is highly unlikely for the fuel to last beyond two years(martian) because the amount of fuel is limited.

[edit on April 7th, 2009 by peacejet]

That article mentioned "a range of latitudes" which would make using the RTG as a power source in lieu of solar panel even more attractive.

The current rovers are relegated to near-equatorial locations so they can take advantage of maximum daylight on a consistent basis. Daylight hours in the non-summer seasons in the higher latitudes would not be enough to provide the power needed for an extended mission.

Throw in the fact that the MSL's power requirements will be greater than the current solar-powered rovers, and it seems that an RTG power system is the best way to go.