NASA has finally unveiled its plans for carrying out the ambitious space exploration programme that was announced by President Bush in January 2004 but left vague ever since. The proposed new space vehicles look like a sensible way to put astronauts and cargo into space after the shuttle fleet is retired and will be built to facilitate landings on both the Moon and Mars. Michael Griffin, the new administrator of the National Aeronautics and Space Administration, deserves credit for this. But, the new plan lacks the pizzazz to inspire public support.

NASA calculates that the new vehicle should be 10 times safer than the shuttle, with perhaps a 1 in 2,000 chance of a catastrophe. The plan pays only the barest lip service to international cooperation; Europe, Japan, China and India all have lunar programmes of one kind or another under way. Given that most experts say international collaboration will be imperative on a high-cost mission to Mars, it would seem desirable to enlist international partners very early.

Also, it ishard to see how NASA can complete all the tasks on its agenda while operating on a constrained budget. Cost overruns may stretch out the completion dates, and leave the exploration vision a more distant prospect.