WASHINGTON - Faced with skyrocketing cost overruns in the International Space Station program, an aging space shuttle fleet that needs replacement, and a budget that is flatlined, NASA is being targeted by the Bush Administration for an overhaul.

Viewed as an early warning signal for the need to install new leadership at NASA is the purging of George Abbey from his powerful post as director of the NASA Johnson Space Center (JSC) in Houston, Texas. As the space agencys lead center for human spaceflight, JSC is primarily responsible for the International Space Station and the space shuttle program.

But the implications of Abbeys ouster, say SPACE.com government and private sector sources, foreshadows even tougher times ahead for he civilian space agency.

To some observers, NASA problems in space station cost overruns and the agencys own inability to control the Johnson Space Center did spur Abbeys downfall.

Those facts are a given as to why Abbey was ousted, said Lori Garver, former associate administrator for NASAs Office of Policy and Plans, who left that position last month.

"I think people certainly have had it out for George Abbey for a while. The point is here, when you have such a serious problem that NASA is in, somebody had to take the blame. So the fingers were pointed and George has taken a fall," Garver said.

Now president of Capital Space of McLean, Virginia, a consulting group, Garver said this is "not a day for NASA to celebrate."

"The space station is tough, and we always knew it was going to be tough. This is not the first time that it has been over budget. Its akin to the pyramids being over budget. When youre doing something like this, things are going to happen," Garver told SPACE.com .

A government source familiar with the decision to re-assign Abbey, disagreed.

"George Abbey deserves much praise for fostering a safety culture that resulted in ensuring that safety is the number one priority throughout JSC programs. That is a major achievement. But with the emphasis now on the need to focus on the future and to put in place some innovative reforms, ranging from space shuttle and space station-related projects, to the development of next generation space transportation projects, it is an opportune time to put in place new leadership."