Today the LCROSS mission launched from Cape Canaveral in Florida. On October 8th it will intentionally smash into the Moonâ€™s south pole. The resulting debris cloud will be analyzed for traces of water, as hidden valleys at the Moonâ€™s poles are thought to contain large amounts of water. If so, then these could be used by future lunar exploration stations. Thus LCROSS is very much a preparatory mission for manned missions to the Moon.
To which I say â€œheart in the right place, but misplaced science priorities.â€ We need to admit here that the reason for space exploration is science. We must also admit that, in space, robots are better at science than we are. Human space travel is a bad idea for many reasons:
- Space is dangerous. Itâ€™s full of radiation from the sun, including cosmic rays. There is no realistic way to shield them. Long-term space exposure will eventually cause death by radiation.
- Space is cramped. Unbelievably claustrophobic. We have been acclimatized to the bright and cheery bridge of the Starship Enterprise, but the reality is about two cubic meters per person. Have you ever seen the Apollo 11 capsule at the Smithsonian in Washington? Six months to Mars and back in a container this tiny? This way lies madness.
- A manned mission requires a return journey. This requires double the fuel & resources.
- Politically, dead astronauts are very bad. What happens during an 18-month manned mission when an astronaut develops appendicitis or an aggressive kidney infection?
- Manned missions cost several orders of magnitude more than a robotic mission. The extra systems and personnel required to keep fragile humans alive are daunting.
In contrast, robotic missions are a piece of cake. While not cheap in absolute terms, they cost a fraction of a manned mission (even a manned mission to the International Space Station). Recent missions have been fabulously successful: Cassini, Mars Rovers, Galileo, Ulysses, Deep Impact. Several other missions are en route to their destinations with all systems go: Messenger, New Horizons, Dawn.