President Bush's announcement of a new US vision for the exploration of space should be the opportunity for a truly multinational effort

Reaction to US President George Bush's unveiling of plans to return to the Moon has been predictably mixed, ranging from applause for his articulation of a vision for human spaceflight to arguments that America has more pressing Earthbound priorities. Response overall was positive but cautious, as there are many unanswered questions. The questions will be framed by the president's forthcoming budget request, which will reveal just how much NASA will have to give up to realise Bush's vision.

At first glance, the White House plan looks like a carefully constructed redirection of NASA's priorities towards the goal of establishing an "extended human presence" on the Moon by 2020, as a jumping off point for a manned mission to Mars at some undefined date in the future. In theory, there should be no need for the technological leaps and technical compromises that characterised the Apollo programme and the Space Shuttle.

The plan envisages a series of robotic missions to the Moon, beginning in 2008 to explore the lunar surface and prepare the way for manned missions of increasing duration beginning as early as 2015. The enabler for these missions will be the Crew Exploration Vehicle (CEV), a recasting of the already planned Orbital Space Plane intended to replace the Space Shuttle as the primary means of crew transport to and from the International Space Station (ISS).

As envisaged, the CEV will be a modular spacecraft that would first fly in 2007-8 as an unmanned crew rescue vehicle, beginning manned flights as a two-way crew transfer vehicle in 2013-14, then evolving to carry humans to the Moon and beyond. Appropriately for the "back to the future" theme of Bush's return to the Moon plan, the CEV is likely to bear a strong resemblance to the Apollo command module.

The biggest questions about the plan are not technical, but financial - how much will it really cost? The only figure given is the projected cost for the first five years - $12 billion, of which only $1 billion will be added to NASA's budget. The other $11 billion is to be found by reducing spending on the Shuttle and ISS. Much more will need to be spent after the first five years, and after Bush has left office, even if he wins a second four-year term as president. The plan assumes NASA's budget, which has decreased over the past decade, will increase in line with inflation until at least 2020.

Bush has made clear that the Shuttle will be returned to flight as soon as possible, now likely to be 2005, but will be retired as soon as assembly of the ISS is complete in 2010. That will leave at least four years when the USA will be dependent on its international partners to carry crew and cargo to the Station. The plan makes clear also that the USA will stop funding the ISS in 2017, presumably when its base of operations moves to the lunar surface. Either the USA plans to abandon its hard-won foothold in low-Earth orbit or, equally difficult to believe, it intends to hand over responsibility for maintaining an orbital presence to its international partners.

Those international partners have made encouraging noises about the US president's vision for space exploration, but they would be well advised to move forward carefully. There is no doubt, given the relatively modest amount by US standards to be invested in the Bush plan, that more could be achieved, more quickly, if Europe, Japan, Russia and others put their backing behind it. But it cannot have escaped the notice of potential partners that Bush portrayed a return to the Moon as an American endeavour, and only mentioned the potential for international co-operation briefly near the end of his 14 January speech.

Europe, Japan and Russia all have their own plans for missions to Mars. China and India have ambitions of reaching the Moon. It is too early for those blueprints to be torn up and replaced by photocopies of the Bush agenda. It would be better for space agencies around the world to seek first to co-ordinate their plans. There is probably great potential for sharing information and avoiding duplication without having to cede all independence of action to a US-dominated international endeavour.

Bush has laid out a careful stepwise-approach to space exploration, but not every step need be taken first by the USA. Space is no place for a race, and human spaceflight is not a competition sport. The costs are enormous and the risks immense. The USA has shown a way ahead; it is time to decide whether to turn away, follow behind or walk side-by-side along the road to the Moon and beyond.

Source: Flight International