The Mars Science Laboratory rover, Curiosity, landed on Mars on August 6, 2012. All thanks to the modern power supply of Curiosity, the MMRTG, it is planned to keep exploring the Martian landscape well into 2026, if not longer. The MMRTG (short for Multi-Mission Radioisotope Thermoelectric generator) is very reliable and gives the rover a constant supply of energy for its electronic instruments. The concept behind the MMRTG is very simple: inside is a radioactive material, plutonium-238 dioxide, which emits heat. The heat produced is captured by a special machine which uses the heat for creating electricity. Any excess heat is used for warming the rest of the rover from freezing any of the instruments due to the cold, -63 °C (-81 °F) , atmosphere of Mars.
Typically, a mars rover is outfitted with solar panels for its main source of power, such as Spirit and Opportunity. The solar panels would provide a good amount of power during daylight hours, but it would receive no power during the night and dust would decrease its overall output. This made solar panels very inconsistent and communication with the rovers limited, unlike the MMRTG on Curiosity, which provides electricity to the rover at all times.
However, the one drawback of the MMRTG is that it will output a little less power over the years, since the radioactive material inside is constantly decaying. On the upside, it is expected to provide sufficient power for at least the next fourteen years. So expect to hear about Curiosity’s accomplishments as it keeps exploring the cold landscapes of Mars day and night.
Sources: http://nuclear.gov/pdfFiles/MMRTG.pdf
http://www.solarviews.com/eng/mars.htm
http://marsrover.nasa.gov/mission/spacecraft_rover_energy.html
Engineering group: Michael Molina, Marina Malaga, Nicolas Delloca, Andy Alfonso
