Orbital Sciences Corp.

An artist's conception shows Orbital Sciences' proposed space vehicle making a rendezvous with the International Space Station.

Several industry teams — reportedly including Orbital Sciences and Virgin Galactic — are vying to build new crew-worthy spaceships for NASA's use.

Today was the deadline for companies to provide NASA with proposals for spacecraft that could transfer astronauts to and from the International Space Station. Such spacecraft would help fill the gap left by the expected retirement of the space shuttle fleet next year. The call for proposals follows up on an earlier round of $50 million in funding that's being disbursed under NASA's Commercial Crew Development program, or CCDev. This round is known as CCDev 2.

The companies making CCDev 2 bids weren't required to announce publicly what they were doing, but a few companies have confirmed their participation:

SpaceX

SpaceX's Dragon capsule, shown here in an artist's conception, has had an initial test.

SpaceX spokeswoman Kirstin Brost told me today that "we filed a proposal" for CCDev 2 funding. SpaceX did not participate in the first round of CCDev work, in part because there wouldn't have been enough money available to do what the California-based company needed to do to upgrade its Dragon capsule for crewed flight. However, SpaceX is receiving $278 million from NASA under a separate program to develop a space cargo delivery system, known as Commercial Orbital Transport Services or COTS. Just last week, SpaceX's Falcon 9 rocket and the Dragon aced their first COTS demonstration flight.

Boeing

An artist's conception shows Boeing's CST-100 orbital capsule.

The Boeing Co. sent out a news release confirming that it submitted a proposal to push ahead with development of its CST-100 spacecraft. It is already receiving $18 million in CCDev funding from NASA for the project, which envisions a seven-person capsule that can be used up to 10 times. Among Boeing's partners are Bigelow Aerospace, a Nevada-based venture whose inflatable space modules could serve as additional destinations for the CST-100; and Virginia-based Space Adventures, which would arrange orbital transport packages for spaceflight participants who would pay their own way.

Orbital Sciences Corp. "did submit a proposal for Commercial Crew Development 2," company spokesman Barron Beneski told me today. Virginia-based Orbital is receiving $171 million under the COTS program to develop its Taurus 2 rocket and Cygnus cargo capsule, but it didn't participate in the initial CCDev round. Beneski declined to tell me anything else about Orbital's proposal, other than to say "we intend to comment on it later this week."

Space News reported that Orbital was teaming up with Virgin Galactic, the New Mexico-based suborbital space company that's backed by British billionaire Richard Branson. The publication said Orbital's craft would be a lifting body capable of carrying four passengers initially, with an option to carry up to six later. The craft would be launched toward the space station from Cape Canaveral Air Force Station in Florida atop an Atlas 5 rocket, and make a runway landing back on Earth at the end of its journey.

California-based Scaled Composites is currently testing Virgin Galactic's SpaceShipTwo rocket plane as well as the White Knight Two carrier aircraft for future suborbital space tours. Space News said that Virgin would sell commercial seats on Orbital's craft, and ferry the spaceship between its landing strip and the Cape using White Knight Two. Such an arrangement would follow through on Branson's stated aspirations to get involved in orbital spaceflight.

Sierra Nevada's Dream Chaser would be a lifting body, as shown in this artist's conception.

Tonight, Space News added yet another nugget: It said Virgin would announce a separate CCDev 2 bid that's led by Sierra Nevada Corp. That Nevada-based company is receiving $20 million in CCDev 1 funds to work on its Dream Chaser space glider. Moreover, SpaceDev, a Sierra Nevada subsidiary, is already working on the hybrid rocket engines that are to be used on SpaceShipTwo. Last week, Aviation Week reported that Sierra Nevada was looking at NASA's mothballed X-34 space plane prototype as a testbed for the Dream Chaser development effort. Ironically, the X-34 started out as an Orbital Sciences project for NASA.

There are lots of questions yet to be answered about these proposals — and more generally about CCDev 2:

• Who else is in the running? Besides Boeing and Sierra Nevada, the other companies funded under CCDev 1 include Blue Origin, Paragon Space Development and United Launch Alliance. Some of the other players in the CCDev competition may make themselves known in the days to come, but they're under no requirement to do so.
• How much money is at stake? NASA has said it expects to award about $200 million during this round of funding, but that's dependent on how much money is appropriated for the program by Congress.
• When will these new spaceships be flying? Orbital is reportedly talking about test flights as early as 2014. SpaceX has said it could have its crew-capable Dragon ready within three years after striking a deal with NASA, which would imply a potential 2014 time frame. Sierra Nevada is also targeting 2014 for the Dream Chaser's first flight. And Boeing says it expects to begin crewed flights of the CST-100 by 2015. So under the current best-case scenario, NASA would be facing a three-year gap between the retirement of the shuttles and the start of commercial crew missions.

NASA is due to announce who gets the money in March.

Update for 3 p.m. ET: Orbital Sciences has issued a news release confirming that it submitted a proposal calling for the development of a "blended lifted body" that could be launched on United Launch Alliance's Atlas 5 or other expendable rockets. "The design derives from studies performed by Orbital for NASA under the Orbital Space Plane program between 2000 and 2003," the company said.

The spaceship would seat four astronauts, as reported by Space News. Orbital said its major suppliers would include Thales Alenia Space, Northrop Grumman, Honeywell and Draper Laboratory and United Launch Alliance. I've added an artist's conception of the Orbital blended lifted body to the top of this item.

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