Mars Rover Curiosity Is Nuclear Powered

Some environmentalists protested the launch of the nuclear powered Cassini space probe destined for Saturn some years ago.  There isn't as much attention being given to the launch of the plutonium-powered Curiosity Mars rover.

Radioactive plutonium, which is used to power the new rover is in a layered, protective module that NASA and others have built to contain the plutonium fuel. The plutonium fuel includes four large pellets, which are clad in iridium, the second densest element known to man. Iridium is both strong and pliable. It bends but does not break. The iridium cladding, which has a melting point greater than 2,000 degrees Celsius (3,632 Fahrenheit), protects the radioactive fuel from impact and heat damage.

The iridium-clad pellets are divided into two pairs, and then the pairs are placed into enclosures called graphite impact shells, or GIS. The GIS are “about the size of a salt shaker” and provide impact resistance. Further heat protection is provided by wrapping the two GIS in insulating sleeves made of a thin fiber called carbon bonded carbon. The shells go together into a hardy, monolithic block called an aeroshell.

The plutonium dioxide fuel is very similar to ceramic. Despite the apparent low radiation risk from the mission launch, NASA, the State of Florida and other federal and local agencies around Kennedy Space Center are making preparations to respond to any launch accident. These precautionary measures will include alerts to direct people to shelters if necessary.

The public supports the concept of Star Trek's enterprise using nuclear powered matter/antimatter 'engines,' but such 'engines' would have ultimately involved lifting radioactive elements into Earth orbit for assembly.  NASA's pursuit of proving spontaneous generation of life will probably once again end in proving just the opposite. (Space .com, 11/23/2011)