Updated

NASA's staff will study whether the space shuttle program could continue operating past its scheduled retirement in 2010, according to an internal e-mail sent this week.

The e-mail obtained by The Orlando Sentinel describes NASA Administrator Michael Griffin's order for a study to determine if the shuttle could fly until 2015, when NASA's next-generation space platform is expected to be completed.

"We want to focus on helping bridge the gap of U.S. vehicles traveling to the ISS (International Space Station) as efficiently as possible," wrote John Coggeshall, manager of manifest and schedules at Johnson Space Center in Houston, in the e-mail sent Wednesday.

• Click here to visit FOXNews.com's Space Center.

NASA officials confirmed the e-mail's authenticity, but said it was too soon to say what the study's reach would be.

"The e-mail did go out," spokesman John Yembrick told The Associated Press. "The e-mail is premature. The parameters of the study have not yet been defined."

Griffin has previously opposed extending the shuttle program, which first launched in 1981, because the money and effort required to do so would hurt progress with the new Constellation launch platform for future orbital flights and proposed lunar missions.

The study comes amid economic and political concerns about the end of a program that has brought thousands of jobs and billions in spending over decades to Cape Canaveral, Houston and other places where shuttle components are produced.

Republican presidential candidate John McCain was one of several senators asking NASA to delay ramping down the shuttle program for at least a year. Democratic nominee Barack Obama has called for $2 billion for NASA to extend the shuttle past 2010.

Yembrick said with the letter from McCain and a new presidential administration coming, "we need to be prepped for this question coming."

And some are concerned that the current stopgap plan — buying Russian spacecraft — is unwise considering diplomatic tension with Russia highlighted by conflict in the former Soviet Republic of Georgia.

Griffin has repeatedly raised the issue of how much it would cost to keep the shuttle flying. Last year, he estimated it could cost $4 billion each year past 2010.

"Continuing to fly the Shuttle beyond 2010 does not enhance U.S. human spaceflight capability, but rather delays the time until a new capability exists and increases the total life cycle cost to bring the new capability on line," he told Congress in November.