(MSL “Curiosity” going through its paces at JPL)
What do you do when you’re mission to Mars is successful beyond belief or expectation? Do it again, bigger, better and for longer, of course! Which is exactly what NASA is doing this week with the launch of the Curiosity Rover under the mission title Mars Science Laboratory.
The new rover is really head and shoulders above the golf cart sized Sprit and Opportunity rovers. It has twice as a many science interments and weighs in at 15 times the little probes weight. It is currently scheduled for launch on Saturday, November 26th.
Curiosity is also expected to have a much longer mission life, where the previous probes were expected to only survive for three months, this probe has a mission time of two years, and in all likelihood will extend beyond that as well. But probably not as long Opportunity has.
The reason for this is that MSL is not solar powered like the previous rovers. It carries a plutonium power pack that uses the radioactive decay to generate electricity through thermal conversion. The core of this battery is ten pounds of plutonium.
That is not an inconsequential amount of the highly toxic and radioactive metal but this is not the first time that such batteries have been used and NASA feels it is comfortable with the chances of launch failure and the procedures it has in place for dealing with the release of any contaminates.
In addition to that change the MSL will not be landing in the giant inflated golf ball that cushioned Sprit and Opportunity. This new rover is so heavy that this method will just not work.
Instead it will be lowered to the surface with a rocket “sky crane”. Basically the probe will dangle at the end of some very long tethers. The rocket will fire to decelerate the craft to stop and then it will detach from the tethers a few inches above the ground.
This is not all that different from what the landing procedure of the earlier rovers, which were slowed by rocket, then released to bounce to a stop. Of course it opens the MSL up to new problems but given the 2.5 billion price tag for this mission I am fairly confident that NASA is very confident on this solution.
Once the probe gets to the Gale Crater it will start its work. Not since the Viking probes in the mid-1970’s has a probe been sent specifically to work on the question of life on Mars. Even this mission will not be looking specifically life itself but rather look at all the places in the crater that seem to have water in their past and there are a few.
The first place will be in what looks like a alluvial fan, which most likely formed by water flowing at some point. Then it will tool on over the spike in the middle of the crater that seems to have both clays and sulfates in the layers around the bottom. Both of those form in water.
The whole idea of this mission is to try to narrow down if there was a time when there were the conditions needed for life on Mars and where it would be best to look in future missions.
To do this the MSL is equipped with cameras, drills and even analysis equipment to take samples and break them down right there on the surface. As with most NASA missions it will also be proving out new technology and developing the mission requirements for future probes.
All of this leads to the goals of being able to send probes that will retrieve samples from the Red Planet and eventually humans to do the same. If Curiosity is even half the success that Sprit and Opportunity were, then it is sure to not be the last probe of this type we send.
The floor is yours.