After months of speculation it now seems that President Bush will announce next week plans to revitalise and refocus the US space effort, bringing back the Moon and Mars into reach of a manned programme.
By Dr David Whitehouse
BBC News Online science editor
It is an initiative he has been discussing for a while, but has waited until the successful landing of the Spirit rover on the Red Planet to make it public.
Harrison Schmitt and Eugene Cernan were the last humans to walk on the lunar surface
Speaking to reporters aboard Air Force One on Thursday, White House Press Secretary Scott McClellan said that after the Columbia tragedy Mr Bush made clear his desire for US space exploration to continue, but not in the same way.
"The president directed his administration to do a comprehensive review of our space policy, including our priorities and the future direction of the programme, and the president will have more to say on it next week."
But McClellan would not say more. Some US space agency (Nasa) officials have said privately they are excited at the prospect of a new direction. Others will not be so pleased.
Back to the Moon, back to stay?
As President Bush's father demonstrated, when standing on the steps of the National Air and Space Museum in Washington in 1989 - at a ceremony to mark 20 years since the first moonlanding - fine speeches do not a space programme make.
His speech was inspiring and well-received. But President Bush senior's "back to Mars" initiative was so costly it sunk under its own weight.
This time, however, it could be different. Many are fed up with the International Space Station (ISS) and the space shuttle.
Some commentators regard the ISS as too costly and unfocused; and politically it has failed to grasp the US public's imagination.
Over the years the space shuttle has been a growing problem, chiefly because it consumes so much of the US space effort's resources.
For some, given the current level of funding, it has become an obstacle. It's good that it can get astronauts into space, they say, but what happens next?
A plan comes together
The problem, it has been argued, is that the ISS and the space shuttle do not go anywhere. Many are saying that to fire up the public's imagination and support, space needs a destination - and there are only two options.
Those options are the Moon and Mars. But how do you get there?
First, streamline the current effort and release much-needed money.
Going to Mars would be an altogether more daunting prospect
This will mean scaling down the ISS and putting the troubled space shuttle into early retirement.
This would mean Nasa finally having to get its act together regarding a space shuttle replacement - an on-off drama that has staggered on for years, consuming billions of dollars, and generally getting nowhere.
The first destination will be the Moon, just a three-day space trip away, as opposed to three years to Mars using conventional rockets.
Back to the Moon would provide a focus and a destination for the US manned space effort that could be achievable within 10 years.
A manned mission to Mars would be far more costly and difficult. But if it is dependent upon going back to the Moon - where technologies could be tested - it would be politically acceptable, as the public payoff would come relatively soon.
A major turning point
In recent years, when Nasa's Mars scientists have been asked about manned missions, their response has always been to talk about their programme of robotic reconnaissance.
On one level this will not change - such reconnaissance would be necessary ahead of any manned mission to the Red planet. But I understand the emphasis will soon change.
Officially supported manned missions, to the Moon and Mars, will become the overtly stated talking point.
And perhaps this way, the US space initiative will regain some of the verve it lost when the last man left the Moon in 1972.
Speculation about what presidents will say is a pointless pastime, especially for science correspondents, and we have been in the position before when politicians and space officials have said (without wanting to be named) that a new dawn is coming.
We will have to wait and see. But next Wednesday could mark a turning point in the manned exploration of space.