Once the smoke clears from the three-year debate over U.S. space policy ushered in by the return of a Democratic administration to the White House, NASA's human-spaceflight activities will look a lot like those planned and started under the preceding Republican administration.

As was the case then, astronauts will fly to the International Space Station (ISS) on Russian Soyuz vehicles while they wait for a new capsule/launch vehicle combination that owes more in basic design and operation to Apollo and its predecessors than to the space shuttle. And NASA will be working on a heavy-lift rocket comparable to the Saturn V, hopeful that it will take humans beyond low Earth orbit (LEO) someday.

Perhaps the biggest difference in the old approach and the new will be the time lost while the politicians and contractors sorted out the details. And only time will tell if the new approach is faster—and cheaper, as NASA's leaders promise.

The initial operational capability of the Constellation program's Orion/Ares I crew-launch stack endorsed by former President George W. Bush was a moving target. Its ambitious schedule slipped as the inevitable technical issues arose without adequate funding to fix them.

To date, the commercial replacements for Orion/Ares I favored by President Barack Obama have not hit major technical challenges like the thrust-oscillation issue that slowed Ares I. But that could be because they have not gotten far enough along in development to run into real trouble. Like Constellation, they are working to optimistic time lines, but they started later.

After Obama took office in 2009, his space-policy team surprised Congress with a budget request that terminated the Constellation program outright, including both the Ares I crew launcher and the planned Ares V heavy-lifter. The new plan handed to the private sector the job of transporting cargo and crew to the ISS. The budget request, delivered without preamble or detail to lawmakers accustomed to a more collaborative approach to working with the executive branch, triggered a strong negative reaction from senators and representatives.

Among them were influential members such as Sens. Bill Nelson (D-Fla.), Kay Bailey Hutchison (R-Texas) and Richard Shelby (R-Ala.) and Rep. Ralph Hall (R-Texas) with serious constituent interests in maintaining the publicly backed jobs Constellation provided, and other members from both parties who had given their good-faith endorsement to the old program.

The 2011 NASA budget request, and the administration's ham-handed approach to dealing with the negative congressional reaction, added to the “gap” in U.S. human spaceflight capabilities that already was an issue on Capitol Hill. The dispute culminated in the compromise NASA Authorization Act of 2010, a three-year measure enacted and signed by Obama in December 2010. Under the legislative process, funding would be covered in a separate appropriation.

The reauthorization legislation essentially called for a shift of funds from the open-ended technology-development program NASA wants to fast-track development of a heavy-lift rocket able to launch 130 metric tons. The technology program, part of Obama's original request, is designed to advance readiness levels for a wide range of technologies that will be needed to send humans on exploration missions beyond LEO. The heavy-lift Space Launch System (SLS) and a Multi-Purpose Crew Vehicle (MPCV) derived from Constellation's Orion capsule are intended to place enough hardware into LEO to move beyond it.

That is pretty much where the government side of human spaceflight remains today. Funding for the authorization act lagged as Congress fought out larger issues before handling fiscal 2011 appropriations in a series of continuing resolutions that essentially maintained spending at fiscal 2010 levels. As a result, the Constellation program was not officially terminated until June 10.

Today NASA spaceflight chief William Gerstenmaier's main concern is transporting enough cargo to the ISS to sustain a six-person crew. He cannot do it with anything flying after the shuttle, so he pushed hard for the STS-135 mission on Atlantis that is now under way to carry one final load of supplies to the ISS and buy time for the commercial companies to finish their cargo carriers.

Right now it looks like Space Exploration Technologies Inc. (SpaceX) has the best chance of doing that with its Falcon 9/Dragon cargo variant. The idiosyncratic private startup has used the dot-com deep pockets and business savvy of founder Elon Musk—plus the lion's share of NASA's $500 million Commercial Orbital Transportation System (COTS) effort to establish a space-transportation industry—to orbit a Dragon from Cape Canaveral and recover it off the California coast.

That was a private-sector first. But SpaceX's finances and the exact technical status of its vehicles remain hidden from view. The public-sector Ares I and Orion developments were more transparent until Obama terminated them as “unsustainable,” in the words of the outside panel headed by former Lockheed Martin CEO Norman Augustine commissioned by Obama to study the issue. That transparency left the projects open to criticism, not all of it constructive or even objective.

There's a little more visibility into Orbital Sciences Corp.'s (OSC) effort to combine the COTS seed money with its own technical skills and funding, and those of an international array of subcontractors, to develop the Taurus II/Cygnus combination for cargo deliveries to the ISS. A team that includes 50-60 Ukrainian engineers and technicians is laboring at Wallops Flight Facility, Va., to meld the Ukrainian-built main stage with surplus NK-33 Russian rocket engines; an ATK solid-fuel upper stage; a capsule built in Turin, Italy; and an Orbital-built service module into a vehicle that can fly from the Mid-Atlantic Regional Spaceport on Wallops Island, Va.

Like SpaceX, the company had planned to meet its COTS milestone and deliver cargo this year. But an acceptance-test fire caused by a fuel leak in the plumbing feeding a flight-ready AJ26 engine, as Aerojet designates the NK-33s it has modified, has thrown that schedule into doubt (AW&ST June 27, p. 42).

Gerstenmaier intends the final shuttle mission to deliver enough supplies to avoid reducing the station crew size before Dragon and Cygnus begin cargo deliveries. But cargo is only part of the story. NASA also is funneling seed money into commercial human-rated spacecraft that it hopes eventually will reduce the need for U.S., European, Canadian and Japanese astronauts to reach the station on the Soyuz capsules.

Under the second round of its Commercial Crew Development (CCDev-2) program, the agency has distributed $269.3 million to help add maturity to concepts for private spacecraft to carry astronauts to the ISS. Boeing was the big winner in CCDev-2, awarded $92.3 million on top of the $18 million it received in last year's CCDev-1 competition. Sierra Nevada Corp., last year's top winner, will get $80 million to go with the $20 million it received in 2010.

SpaceX will receive another $75 million to develop a launch abort system and other hardware so the Dragon capsule can carry crew. Blue Origin, the secretive startup organized by Amazon.com founder Jeff Bezos, will receive $22 million to continue work on its vertical-takeoff-and-landing spacecraft.

Boeing is building a capsule designated the CST-100, which would use batteries rather than solar arrays for power on quick trips to the space station. Plans call for enough power storage in the CST-100 service module to enable two docking attempts, and the capsule is being designed to stay at the station for as long as seven months as a lifeboat once it is connected to the station grid.

SpaceX is using its CCDev-1 award to develop a side-mounted pusher-type launch abort system and begin designing crew accommodations for a human-rated Dragon. OSC, NASA's other commercial cargo-delivery provider, decided not to pursue human flight when its reusable spaceplane design did not pass muster in CCDev-2.

NASA is continuing to invest in Sierra Nevada's Dream Chaser lifting-body vehicle as a potential replacement for the shuttle's runway-landing capability. The composite spaceplane is based on NASA's HL-20 experimental vehicle, derived from the Russian BOR-4 test vehicle that flew in space four times.

Blue Origin plans to advance its otherwise unnamed “Space Vehicle” by using the CCDev-2 funding to complete “key system trades,” work with NASA's Ames Research Center to design the vehicle's thermal protection system and conduct the reviews necessary to generate, in the words of its CCDev-2 proposal, “a baseline definition architecture and system requirements.”

Work on the four spacecraft with the CCDev-2 funding is just starting. Blue Origin and SpaceX have held “kickoff meetings” on spending the new federal money, according to a NASA progress report. Boeing completed a system definition review on May 19, NASA says, and Sierra Nevada met its systems requirements review milestone by delivering 10 documents June 1, including its human-rating plan.

By comparison, the MPCV that NASA started as the Orion crew exploration vehicle under Constellation is the most advanced crew carrier in the lineup. Lockheed Martin kept working on Orion after Obama called for cancellation of Constellation under appropriations language that prohibited NASA from terminating the program and its contracts.

According to NASA Program Manager Mark Geyer, Orion has cost the government $5 billion to date. With its portion of that money, Lockheed Martin has built and pressure-tested the initial Orion development vehicle and moved it from its fabrication facility at the Michoud plant in New Orleans to the Lockheed Martin spacecraft factory near Denver for acoustic and other ground tests. It has also developed a telescoped flight-test program using existing launch vehicles that it says could see the vehicle ready to carry crews of four to orbit in 2016. But NASA is slowing that plan to bring Orion development into sync with the heavy-lift SLS Congress has ordered NASA to build (AW&ST May 30, p. 30).

Thus, none of the planned human spacecraft has a human-rated launch vehicle to carry it to space. Boeing has yet to pick a launch vehicle for its CST-100, Sierra Nevada and Blue Origin plan to use the Atlas V and SpaceX will use its Falcon 9.

Meanwhile, Congress and NASA continue to spar over how fast the agency is moving on the heavy-lift rocket ordered in the reauthorization act. Administrator Charles Bolden insists NASA cannot meet its 2016 congressional deadline, no matter how much money Congress appropriates for the task, while lawmakers like Hutchison and Nelson insist that the law is the law. Sen. John D. Rockefeller, 4th, (D-W.Va.), chairman of the Senate Commerce, Science and Transportation Committee, used a subpoena threat to pry loose permission for his staff to see preliminary versions of the SLS reference design, but only if they visited agency headquarters to do so.

That design, selected by Bolden on June 14 and forwarded to the White House for final approval, calls for a heavy-lift rocket that uses liquid hydrogen fuel and liquid oxygen for main- and upper-stage propulsion. Early versions of the rocket would use three surplus space shuttle main engines (SSME) each to power the main stage and the J-2X upper-stage engine started under Constellation for the upper stage. For added thrust during liftoff and early ascent, the vehicle would use a variant of the solid-fuel booster rockets that performed the same task for the space shuttle.

Once the 15 SSMEs in NASA's stockpile are expended, the plan calls for a shift to the reusable RS25E variant that Pratt & Whitney Rocketdyne has proposed. To “evolve” toward the 130-metric-ton capability, and satisfy Shelby and the senators from California with some potential jobs for their constituents, the plan would hold a competition for kerosene-fueled strap-on boosters as more powerful replacements for the shuttle-derived solids.

Aerojet says it already is working in California on an upgraded version of the 340,000-lb.-thrust AJ26 that would generate about 500,000 lb. of thrust at sea level and has entered an agreement with Teledyne Brown Engineering to build the hardware in Huntsville, Ala.

To put it mildly, that work is in its early stages. As technicians at Kennedy Space Center prepare the space shuttle orbiters for transfer to museums in Virginia, California and—once Atlantis lands—just outside the KSC gates, the U.S. human spaceflight program is arguably less defined than it was in November 2008, when the national election upended it.

Inevitably that will change, as test flights and on-going political negotiations play out for good or ill. The gap in U.S. human spaceflight capability continues, with less technical clarity on how it will be closed.

As Atlantis cranks out the final orbits of the shuttle decades, we explore what comes next in the U.S. space program and offer expert commentaries on the value of the shuttle in bringing the U.S. this far. NASA Shuttle Program Manager John Shannon outlines what the money and lives spent on this “incredible learning tool” have given the space program. Michael Griffin, who planned for the shuttle retirement as NASA administrator, discusses why it is time to move on.