The competing space effort, called Jupiter, is being worked on by 57 volunteer engineers and NASA employees.  The Ares team is made up of thousands of NASA engineers and government contractors, with one Ares project manager already dismissing the Jupiter design, saying it won't work.

Last fall, NASA took a look at the Jupiter design, and said it was a flawed plan that simply isn't feasible for real launches.  Until NASA offers a full review, however, workers who are on the Jupiter team are not ready to dismiss their work.

At least one Jupiter supporter has stepped forward to accuse NASA of trying to block information to help limit the success of the Jupiter project.

"Our concern is that by the time everyone figures this out, we will have destroyed our heavy-lift system," former NASA contractor and now supporter of Jupiter Steve Metschan told the Associated Press.   "At the end of the day, all we're asking for is an independent review of all this stuff."

The new design also could help NASA save $35 billion in development and manufacturing costs, at a time when NASA is struggling with budget issues.  NASA anticipates spending up to $230 billion to return to the moon over the next 20 years, with NASA already spending around $7 billion on Ares development.  

NASA officials said they take all proposals seriously, but they haven't found one that is able to compete with Ares.
 
The current generation NASA shuttle retires in 2010, and the Ares rocket won't be available until 2014 or 2015.  NASA research says there is a 65 percent chance of the Ares-I carrying the Orion spacecraft into space by March 2015.  NASA will have to rely on Russian shuttles and space capsules to get astronauts and food supplies up to the International Space Station (ISS).