Orbiting space fuel stations to make missions more feasible

A US presidential panel looking into options for NASA's human space flight programme is looking into a concept that may well make space transportation more feasible than it has been so far: orbital gas stations. The concept, which involves storing rocket fuel in orbit around Earth, opens new vistas for long-distance space travel, a sub-committee of the panel said.

"It is often said that if you want to go beyond LEO (low-Earth orbit, or about 200 miles above the planet) you've got to have a big rocket. I don't think that's right," said Jeff Greason, a member of the space programme review panel and a co-founder of XCOR Aerospace based in Mojave, California.

NASA's current plans for space travel are focussed around designing a heavy-lift rocket called Ares 5 which will have the power to leave Earth's orbit and deliver cargo to the moon. Ares 5 is expected to replace NASA's workhorse shuttle fleet, which will soon retire.

Not surprisingly, the space agency estimates the cost of a programme to land astronauts on the lunar surface by 2020 to be in the region of $108 billion.

Such cost estimates are not feasible for a cash-strapped NASA and so the organisation's moon missions are very likely to be relegated to the mid-to-late 2020 in the most optimistic scenario.

Greason's ''game-changing'' plan sidelines the heavy-lift approach and relies on smaller, existing launch vehicles to deliver propellants into orbiting stations. Under this plan, rocket stages needed for deep space travel can be launched empty, or nearly empty, and be subsequently fuelled in space.