President Obama is expected to defend his vision for NASA and present some revisions to his controversial proposals for the space agency when he visits Kennedy Space Center in Florida on Thursday.
Obama will propose accelerating work on the kind of massive, heavy-lift rocket needed to get astronauts deep into space, beyond the International Space Station. He'll also announce plans to build a scaled-down version of a crew capsule that was part of NASA's big Constellation program -- which his administration wants to cancel.
The crew capsule, called Orion, wouldn't be used to take astronauts up into space, however; it would only serve as a standby emergency escape vehicle for the space station, according to a fact sheet on the planned speech released by the White House. (Read the fact sheet [PDF].)
The speech comes as the Obama administration faces sharp criticism from lawmakers, former astronauts and others for its proposal to kill the Constellation program.
That program was supposed to be the replacement for the agency's aging space shuttles, which are scheduled to be retired later this year. After the shuttles become museum exhibits, NASA will rely on Russia to get American astronauts to the space station until the United States can develop a new way to access space.
As part of the Constellation program, the agency started work on Orion and a rocket to get it to the space station. Constellation also was aimed at returning astronauts to the moon by 2020, as a steppingstone to Mars.
But after a blue-ribbon panel of experts said last year that Constellation had been so underfunded that its goals weren't feasible, the White House laid out a new vision. It centered on extending the life of the space station and encouraging private companies to develop space taxis to ferry astronauts there, so that NASA could focus on developing advanced technologies to take astronauts to new deep-space destinations such as asteroids.
Backers of that plan have said it charts a realistic, sustainable path forward for NASA while supporting the growth of private space travel. Critics have charged that it puts NASA on a mission to nowhere, with no specific destinations or timetables for reaching them. And the thought of abandoning Constellation came as a heavy blow to a space community already worried about the loss of jobs after the space shuttle program ended.
Preserving a scaled-back version of the Orion crew capsule would retain some Constellation jobs, while giving NASA a technology platform for future spacecraft, according to the White House fact sheet about Obama's speech.