The prevailing congressional discontent over U.S. President Barack Obama’s plan for NASA’s human spaceflight program has opened the door for a concerted push on the part of some lawmakers to extend operations of the space shuttle beyond its currently scheduled retirement date at the end of this year.

This was to be expected: The space shuttle program is too job-rich for politicians to let it go without a fight, and the issue continued to smolder even after Congress endorsed former President George W. Bush’s plan to retire the orbiter fleet and develop a replacement system that eventually would be used to return astronauts to the Moon. Shuttle backers were no doubt mollified by the fact that the former president’s program, dubbed Constellation, made use of key space shuttle components and infrastructure and promised to provide jobs in many if not most of the districts affected by the orbiter’s retirement. In doing away with Constellation while sticking with previous plans to mothball the shuttle fleet, the Obama administration breathed new life into a cause that had gone dormant.

On March 3, U.S. Sen. Kay Bailey Hutchison (R-Texas) introduced legislation that would keep the orbiter fleet flying at least through 2012. A companion bill was introduced in the House by Reps. Suzanne Kosmas (D-Fla.) and Bill Posey (R-Fla.).

Adding fuel to the fire were remarks by John Shannon, NASA’s space shuttle program manager, who told reporters March 9 that, contrary to assertions that production closeout of shuttle-related items had in many cases reached the point of no return, all it would take is money to keep the fleet in service beyond 2010.

In a later interview, Mr. Shannon backpedaled a bit, noting how expensive the shuttle is to fly, and that restarting shuttle production would require rehiring idled workers who would then have to go through the pain of being laid off again. He stopped short of a complete about-face, however, suggesting that it might make sense to retain the shuttle in the absence of a replacement vehicle.

Actually, Mr. Shannon wasn’t wrong the first time: With enough money, of course it’s possible to extend shuttle operations indefinitely, even if that means restarting idle production lines. The last space shuttle external tank is expected to roll out at the factory this summer; building a new tank is a two-year process, meaning there likely would be a significant gap between the last flight utilizing existing hardware and the next mission. The space shuttle program costs about $2.5 billion to $3 billion annually, whether or not the fleet is actually flying, but yes, with enough money, orbiter operations could be extended for years.

By the same token, NASA with enough money could have executed Constellation as planned, replacing the shuttle by around 2017 — perhaps even sooner — and returning astronauts to the Moon sometime after 2020. According to the Norm Augustine-led panel that reviewed U.S. human spaceflight options last year, Constellation’s major problem was that it was too expensive.

The big problem with extending space shuttle operations is that it only postpones the inevitable, while costing billions of dollars that otherwise could go toward a replacement vehicle and other capabilities necessary to explore space beyond low Earth orbit — something the space shuttle cannot do.

Congress has correctly pointed out that the administration’s current plan for deep space exploration — and to call it a plan at this stage is generous — leaves much to be desired. But if there’s anything that could make the situation worse, it would be if the administration caves to political pressure and significantly defers shuttle retirement. The recent White House announcement that it will host a space conference in Florida — presumably near NASA’s Kennedy Space Center — featuring an appearance by the president has touched off speculation that the administration is planning to do just that. Let’s hope that is not the case: Adding a flight or two that would make use of existing hardware is one thing; initiating production of new shuttle hardware would sink any chance of developing new capabilities to explore beyond low Earth orbit, leaving NASA right back where it was when the 2003 Columbia tragedy prompted the re-evaluation of U.S. human spaceflight strategy and goals that ultimately gave rise to Constellation.

Congress should be focusing its energies not on extending shuttle operations or reinstating Constellation, but rather on working with the administration to come up with a plan that provides a space station crew transport capability sooner rather than later and offers a logical pathway for getting astronauts out of low Earth orbit. One thing everybody can agree on is that to do that, NASA needs a heavy-lift rocket, regardless of whether the destination is the Moon, Mars, an asteroid or someplace else. Such a development program, properly structured, could soften the jobs impact of shuttle’s retirement while providing a needed shot in the arm of the U.S. propulsion industrial base. Without such an effort, any plans for what the Augustine panel characterized as meaningful space exploration will lack credibility.