I went to see The Martian this weekend, the movie with Matt Damon as the astronaut stranded on Mars.
I don’t really want to review the movie here, I would just like to talk about the scene in the movie where he digs up a RTG that the astronauts had buried previously and marked with a scary flag as a warning to anyone who might stumble across it, you know radioactivity and all.
Here is a photo of a real RTG powered by plutonium 238. This one was used on Cassini.
1. Plutonium 238 is an alpha emitter. These particles can be stopped by a sheet of paper. Real RTGs have sheet metal shielding. Humans can safely be next to these without any worries. (see the photo above.)
2. The radioactivity of the plutonium 238 releases enough energy to make itself red hot from the heat.
3. The heat is harnessed to produce electricity directly with hundreds of thermocouple junctions.
4. RTGs have been used in deep space probes for decades. They will continue working when the light from the sun is very dim and solar panels aren’t feasible.
That being said, there is no reason for the movie astronauts to have buried the RTGs. They would still be working day and night producing electricity and heat for the astronauts. The rover shown on the movie should have been powered by RTGs. Then, Mark Watney (Matt Damon) could have driven the rover day and night.
Furthermore, serious adults who consider actual Mars missions include nuclear power in their plans, both for propulsion and for heat and electricity.