WASHINGTON — The compromise NASA authorization bill passed by the U.S. House of Representatives Sept. 29 approves key elements of U.S. President Barack Obama’s proposed new direction for the U.S. human spaceflight program, providing support for government sponsorship of commercial astronaut transportation services while effectively sealing the fate of the Ares 1 crew launch vehicle that was several years in development.

But much of what lies ahead still depends on congressional approval of a separate bill that appropriates funds for NASA in 2011, something that is not likely to happen before the elections in early November.

The $58 billion, three-year NASA authorization bill drafted and approved by the Senate earlier this year cleared the House amid contentious bipartisan wrangling over the future of NASA’s human spaceflight program. NASA Administrator Charles Bolden was quick to spin its passage as a clear mandate for carrying out Obama’s plan to extend the international space station program to 2020 and foster development of private vehicles for astronaut transit in low Earth orbit.

“This important vote today in the House of Representatives on a comprehensive NASA authorization charts a vital new future for the course of human space exploration,” Bolden said in a statement following the bill’s passage late Sept. 29.

The bill, which at press time was awaiting the president’s signature, clears the way for NASA to kill Ares 1, a centerpiece of the Moon-bound Constellation program the White House marked for termination in February. But the fate of another Constellation project, the Orion Crew Exploration Vehicle, remains uncertain, and the bill also calls for development of a heavy-lift rocket that was not in the administration’s plans.

Authorization bills provide policy guidance and offer recommended funding levels for congressional appropriators to consider in crafting their funding bills. NASA officials expect a new funding bill to be approved before the upcoming holidays, but in the interim, the agency will operate through Dec. 3 under a continuing resolution that mandates continued funding for all federal programs, including Constellation, at levels no greater than appropriated in 2010.

NASA Deputy Administrator Lori Garver said the new authorization bill does not allow NASA to cancel Constellation contracts or initiate “entirely new starts” until a 2011 appropriations bill is signed into law, but it does inform how NASA operates under the continuing resolution.

“We know we want to structure our programs going forward to align generally with what we’re given in this bill, so it’s going to really help clarify, I think, and inform the [continuing resolution] as we go forward,” Garver told reporters during a Sept. 30 news conference. “People have talked in the past about ‘Oh, we’re just throwing this money away on these old programs.’ We’ve never felt that is being done because these are technologies and these are employees who are valuable to the nation. But we definitely feel now we can direct them with more clarity from this bill.”

NASA spokesman Bob Jacobs said in a Sept. 30 e-mail the agency is “not taking any proactive steps to minimize funding on any of the Constellation activities,” but that the absence of recommended funding levels for Ares 1 in the authorization bill means development of the rocket will not continue.

However, “depending on the eventual heavy lift architecture, there could be common technology applications,” he said.

Although Obama planned to pursue a stripped-down version of Orion for use as an astronaut lifeboat on the space station, the authorization bill directs NASA to continue developing the capability to conduct the sort of deep space missions for which Orion was originally designed.

“Orion will continue. However, there’s an ongoing assessment on how that program will transition from the initial design to one that can serve as a crew rescue vehicle as part of its evolution into a spacecraft that can carry astronauts beyond low Earth orbit,” he said, adding that while NASA has discussed the possibility of demonstrating an Orion lifeboat capability as early as 2013, there is no money in the budget to pay for it.

“The current design of Orion will have to be adjusted for it to serve as a [crew rescue vehicle],” he said. “Those discussions are under way and the development path isn’t yet known.”

While Obama planned to defer work on a new heavy-lift rocket for missions beyond low Earth orbit, the authorization gives NASA 90 days from the bill’s enactment to settle on a design and begin work on such a vehicle next year. Garver said there is “no question” the bill’s direction to design a shuttle-derived heavy-lift launcher presents challenges for NASA.

However, she said “the trade-space continues to be open on what type of vehicle we will have,” including the potential for a heavy-lifter based on the U.S. Air Force’s existing Atlas 5 and Delta 4 rockets.

“We hope to have new competitions for the new types of things that we’ll be doing with these rockets,” she said during the press conference.

Until then, it is unclear what will happen to NASA’s civil and contractor work force. Shortly before the authorization bill went to the House floor for a vote, NASA officials characterized its swift passage as crucial to the agency’s 18,000 civil servants and more than 100,000 contractors.

“Passage of this bill will really provide a lot of clarity so that the workforce as we go forward can realize there is this amazing future and support; bipartisan support, bicameral support, administration and Congress support,” Garver said during a Capitol Hill luncheon Sept. 29 before the bill was approved, asserting that Obama’s proposed increases to NASA’s top-line spending profile over the next five years will create “a vibrant future” at launch facilities at Cape Canaveral Air Force Station, Fla., and NASA’s 10 field centers throughout the country.

A day later, Garver said passage of the authorization bill does nothing to avert job losses associated with the Constellation “ramp-down” under way before the bill was approved.

“I don’t believe this bill will change the situation regarding the Constellation transition workforce layoffs at this time,” she said. “What we need to do now with this direction and this clarification is start developing the future program so we can quickly start to re-employ to have a more clear, sustainable direction.”

Hours later, Alliant Techsystems announced plans to let go 426 aerospace workers, including roughly 300 at the company’s Utah manufacturing facilities who were attached to the Ares 1 rocket program. Alliant Techsystems is responsible for the Ares 1 first stage, which is derived from the large solid-rocket motors the company has long built for the space shuttle program.

Rep. Rob Bishop (R-Utah) blamed the layoffs  on the inability of lawmakers to approve new spending legislation before the fiscal year’s end.

“Congressional leaders refused to pass a budget or an appropriations bill,” he said in a Sept. 30 news release issued in response to the job losses. “Instead they passed a continuing resolution, a stop-gap measure that keeps government running but does not sufficiently fund programs like Constellation.”

Other layoff announcements coincided with the bill’s passage, including more than 1,000 shuttle workers at United Space Alliance facilities in Florida, Texas and Alabama, and another 800 Lockheed Martin shuttle employees at NASA’s Michoud assembly facility in Louisiana.

Garver noted that the new bill calls for a second round of contracts to be competitively awarded under the agency’s Commercial Crew Development (CCDev) program that could contribute to job growth in the aerospace sector. NASA initiated CCDev in 2009 with $50 million in economic stimulus funding in an effort to seed development of technologies in support of commercial crew transportation systems.

One of the biggest question marks going forward is how NASA will pay for the numerous initiatives called for in the bill, including the launch of an additional shuttle mission next year. Garver said the issue is for congressional appropriators to hash out, but added that she expects “a lot of alignment” between the authorization bill and a 2011 spending measure approved by the Senate Appropriations Committee in July that likely will be incorporated into a larger omnibus federal spending package later this year.

The Senate appropriations bill, S. 3636, provides $620.6 million for the extra shuttle flight, but does not provide sufficient funding to maintain the space shuttle work force and infrastructure through the end of the fiscal year as directed in the NASA authorization.

S. 3636 also provides $3 billion in 2011 to continue Orion development while beginning work on a new heavy-lift rocket for exploration beyond low Earth orbit. While the bill projects a total cost cap for the program of $11.5 billion through 2017, internal NASA estimates peg the cost of building a shuttle-derived heavy-lift vehicle directed in the authorization bill at between $14 billion and $17 billion.