"It's entirely possible that we wake up one day and the Russians say, 'We're not taking your astronauts up anymore,'" said Marco Caceres, director of space studies at Fairfax, Virginia-based consultant Teal Group. "NASA's anticipating this possibility. That's why they want to move as quickly as possible with this program."

Funding two ventures may raise development costs while also fostering competition and giving NASA an alternative if one vehicle encounters technical difficulties, said Marco Caceres, director of space studies with Teal Group, a Fairfax, Virginia-based consultant.

Congressional opposition to a similar arrangement for the crew contract has waned as the fraying U.S.-Russia relationship focuses attention on NASA's dependence on Soyuz rockets to put astronauts into orbit, Caceres said in a telephone interview.

"The Russians have done NASA a favor in terms of funding," Caceres said.

 The announcement put as positive a spin as possible on Gass' departure, but reading between the lines makes it clear leaders at the parent companies felt a change was needed, said Teal Group analyst Marco Caceres.

"Gass hung his hat on ULA's track record of successful launches," Caceres said. But ULA looked complacent when matched against the dynamic Elon Musk, whose SpaceX will shortly begin competing with ULA for military space launches.

Caceres said he expects to see layoffs and a streamlining of ULA to find all possible cost savings.

"My sense is you're going to see at ULA a restructuring of some sort, because ultimately they're going to have to find a way to be a lot more competitive on price," he said.

The GSSAP satellites "could certainly be considered offensive," Defense News reported Marco Caceres, an analyst with the Teal Group, as saying. "Obviously, the US Air Force is primarily thinking of it as defensive or simply from a maintenance and repair standpoint. But if you have the ability to get close enough to other satellites to observe or repair or refuel, then sure, you could probably take them out."

And the RD-180 has its supporters. "There's nothing out there that's better in terms of weight-to-power ratio than the RD-180," said Marco Caceres, an analyst with the Virginia-based Teal Group. "I don't know if you can come up with an engine as powerful as the RD-180 in a short time from scratch. "It's really more about developing the least expensive engine that will make the Atlas V much cheaper commercially."