NASA's Mission to Pluto

Congratulations to NASA for the successful launch of the New Horizons mission to Pluto. This marks the first time humanity has reached out to the solar system's most distant planet. (Well, maybe it's the most distant planet. There's a lot of discussion about that right now.) In any event, the probe is off on its nine-year journey.

Comment: The launch brought out the usual complaints about its use of plutonium to power the on-board RTGs. While any use of nuclear materials must be subject to the most stringent safety precautions, those who call for an end to its employment are ignoring the realities of space flight. The utility of solar panels drops off drastically once you get past Mars. Outer-planet exploration is dependent on nuclear power generation, and long-term exploration with complex spacecraft and humans is dependent on nuclear propulsion. There is no real alternative.