The Mars Science Laboratory mission launched today to deliver the Curiosity rover to Mars in August 2012.
If successful, it will be the fourth such rover to plumb the secrets of the Red Planet. Each successive rover mission has been bigger and more ambitious:
- 1997 – Mars Pathfinder: Carrying the Sojourner rover, which was 65 cm long, had a mass of 10.5 kg, and carried solar panels generating 13 W. As a measure of its computational capacity, it had 176 KB of solid state storage.
- 2004 – Mars Exploration Rover: Carrying the twin rovers Spirit and Opportunity, each of which is 1.6 m long, have a mass of 180 kg, with solar panels generating 140 W for a few hours a day (at the beginning). The rovers have 256 MB of solid state storage.
- 2012 – Mars Science Laboratory: Launched today carrying the Curiosity rover which is 3.0 m in length and has a mass of 900 kg, much larger than the previous missions. Instead of solar panels, it is powered by the thermal energy released by the decay of plutonium-238 using a system called radioisotope thermoelectric generators (RTGs) which will provide 125 W of power. This can be done continuously unlike the solar panels of previous missions which, of course, required sunlight. Therefore, in a given day, Curiosity will generate 2.5 kWh per day whereas the twin rovers could only do 0.6 kWh in a day. The onboard computer will have 2 GB of solid state storage.
Given that the previous Martian rovers were amongst the most successful space missions ever launched, good times ahead are predicted for Curiosity provided its novel delivery system can safely deliver it to the surface.