Many sceptics will undoubtedly question why any country would choose to invest in future space exploration, including a manned mission to Mars, while there are so many unsolved problems on our planet, from HIV to malaria to poverty.

BBC: Viewpoint: Should we send humans to Mars?

The first challenge is to clearly voice a renewed commitment to the broader mission and goals of U.S. cooperative space exploration, not just deploy technical capabilities and, somewhere along the way, rekindle taxpayer support.

FORBES: NASA, Got Space Exploration? Get Goals, Get Funding and Get Uhura.

The lives of these people are very precious to us, and the board considered that very serious matter that these brave people thought that what they were doing was important, that it was significant, that it was part of human space exploration, that the things that were going to be learned from this mission were worth the risk that they were taking.

CNN: Board chairman: Shuttle design safe

Our second goal is to develop and test a new space craft, the crew exploration vehicle, by 2008, and to conduct the first manned mission no later than 2014.

CNN: Bush: 'It is time for America to take the next steps' in space