NASA's plans for human spaceflight, the subject of much hand-wringing since the curtains closed on the agency's space shuttle program in July, took a big step this week when the agency announced plans for a powerful new rocket to take astronauts into deep space. But is the mammoth Space Launch System a step forward or a step backward? That remains to be seen, but there are plenty of reasons to worry.
One concern is hardly new. In fact, it's endemic to NASA and to other federal science agencies: big projects make big targets when it comes time to cut back spending. One need look no further than the past few years to see this principle in action. The fate of the James Webb Space Telescope, a multibillion-dollar observatory designed to succeed and improve upon the venerable Hubble Space Telescope, hangs in the balance as lawmakers in the House of Representatives have moved to kill it. But the more relevant example here is the Constellation program, which sprung from President George W. Bush's 2004 space plan. Constellation was going to be a pair of rockets, one small model and one heavy-lifter, to loft astronauts into orbit and beyond in a new Orion crew capsule. But President Barack Obama killed the plan in 2010 as Constellation staggered under schedule slips and cost overruns.
The bigger worry with the Space Launch System (SLS) is specific to the rocket itself. The SLS was born not on the drafting tables of NASA engineers but in the halls of Congress. Last year President Obama, in laying out his long-term plans for space exploration, had proposed that by 2015 NASA would design a new rocket to explore deep space and would then set to building it. But Congress, in its NASA-funding legislation, decided to press the issue. The NASA Authorization Act of 2010 mandated that NASA begin immediate work on what the law's authors dubbed the SLS, with a 2016 deadline for initial readiness.
The lawmakers even dictated performance metrics for the rocket—an initial launch capacity of 70 to 100 tons, expandable to at least 130 tons—lest NASA should design a rocket to meet its own objectives. Congress also dictated that wherever possible the SLS should include technology from the space shuttle, whose own design comes from the 1970s, and from Constellation. (In fact, some commentators have remarked that the SLS closely resembles the heavy-lift rocket of the troubled Constellation program.)
So why did elected officials decide to play rocket scientist, calling the SLS into existence and sketching out its design by writ of law? A hint can be found in the statement issued Wednesday by NASA. "This launch system will create good-paying American jobs, ensure continued U.S. leadership in space, and inspire millions around the world," NASA Administrator Charles Bolden said. Note that jobs came first, and exploration second. Another clue comes from the fact that Bolden announced the SLS in Washington, D.C., joined by senators Kay Bailey Hutchison of Texas and Bill Nelson of Florida, two states that benefited greatly from the space shuttle program.
If Obama had gotten his way, and NASA had spent a few years planning an entirely new rocket to explore deep space, the space workforce in Florida and Texas would have withered in the interim. Hutchison and Nelson have loudly championed the SLS, going so far as to accuse the Obama administration of trying to "undermine America's manned space program" by not accelerating the rocket's development.
And if NASA had decided to harness new rocket technologies rather than borrowing the old, companies that have long prospered under NASA's human spaceflight program would have suffered. ATK Aerospace in Utah, for instance, makes the solid rocket boosters that once launched the space shuttle, and those same boosters will also launch the SLS. Not surprisingly, Utah lawmakers have pushed for SLS development and its use of solid motors. (The indelible Congressional mark on the new rocket has led some to derisively refer to the SLS as the Senate Launch System.) As is, the SLS is expected to cost $18 billion by 2017.
NASA seems to have pushed back at first. The space agency issued a report in January expressing doubts that the SLS could be ready by 2016 and questioning whether the rocket would meet Bolden's pledge to undertake projects that are "affordable, sustainable, and realistic." Hutchison has not been pleased with such demurrals. "The political leadership at NASA and at [the White House Office of Management and Budget] has dragged their feet on implementation," she said in a statement last month. "After many requests for NASA to comply with the law, the Commerce Committee finally initiated a formal investigation earlier this summer."
In the past, Bolden has noted that the U.S. does not yet have a use for the beefed-up SLS. "NASA does not need a 130-metric-ton vehicle probably before the next decade," he has said. He has also said that NASA would "continue to negotiate and discuss with the Congress why that is not necessary."
Even the initial 70-ton capacity of the SLS is of questionable utility. As Jeff Foust wrote in January in The Space Review, "The debate about how to build [a heavy-lift rocket] will likely raise another question: why build one now?" The stated mission of the SLS is to explore deep space and to provide a NASA-owned option for reaching the International Space Station, which today's astronauts can only access via Russian rockets. But neither job screams out for the SLS that Congress has mandated. "In the case of the latter the SLS is considerably oversized," Foust wrote, before noting that "in the former case the specific transportation needs aren't clear since NASA hasn't settled on a specific exploration architecture." Or, as lunar scientist Paul Spudis put it in a blog post, "In the absence of any specific mission, the payload capacity of your launch vehicle is entirely academic."
Bolden is now supporting the SLS, at least in public, but what choice does he have? The law of the land requires that he build the SLS, regardless of whether NASA needs it—and regardless of whether better options exist for delivering astronauts to Earth orbit and to deep space. From its inception, the SLS has been fundamentally an instrument of politics, not exploration. Whether it can be both is the $18-billion question.