To Mars, with a monster rocket: How politicians and engineers created NASA's Space Launch System

The office of NASA rocket scientist Garry Lyles is located on the campus of Marshall Space Flight Center in Huntsville, Alabama, inside a modern, five-story facility named Building 4220.

This unimaginatively named complex is NASA's design hub for the Space Launch System, or SLS, a giant, heavy lift rocket the agency plans to use to send humans to Mars in the 2030s. Lyles is the rocket's chief engineer. He's been at NASA for 40 years, and is now focused on making sure SLS stays on schedule for its maiden test flight in 2018.

When I visited Lyles last month, there was a model rocket on his desk that looked like a patriotically painted version of SLS. It was all white, with a red nose cone and engine section, and a blue upper stage.

But it wasn't SLS.

"This was Magnum," Lyles said, touching the model with the reverence one might show while flipping through an old photo album.

Designed in the 1990s, Magnum could have hauled around 80 metric tons of cargo to orbit. Though never built, it was remarkably similar to SLS: It would have used space shuttle main engines, two shuttle solid rocket boosters, and a core stage based on the shuttle's external fuel tank.

Magnum had the same destination as SLS, too: Mars.

NASA has been brainstorming ways to send astronauts to Mars with giant rockets for much of the agency's existence. The story of how SLS was born, however, involves a particularly messy tangle of politics and rocket science. 

Need to catch up on our Horizon Goal series?

Part 1: How The Columbia Tragedy Shifted NASA's Sights To The Moon
Part 2: 'Apollo on Steroids': The Rise and Fall of NASA's Constellation Moon Program
Part 3: Space in transition: How Obama's White House charted a new course for NASA

To Mars, with big rockets

Fresh off the moon landings in 1969, German rocket scientist Wernher von Braun, the mastermind behind the Saturn V rockets, unsuccessfully pitched Congress and the White House on a humans-to-Mars mission. A decade-and-a-half later in 1989, President George H. W. Bush endorsed a Mars initiative that ultimately lost support after being saddled with a hastily derived, $500 billion price tag.

Magnum was designed after the latter effort. In both cases, NASA's plans centered around giant, heavy lift rockets capable of carrying massive amounts of cargo into orbit. The concept has precedent: the Saturn V could haul about 118 metric tons to Earth orbit, which enabled Neil Armstrong, Buzz Aldrin and Michael Collins to schlep a heavy crew capsule, lander and ascent vehicle to the moon in just one trip. 

By comparison, the space shuttle's payload capability maxed out at about 25 metric tons, and it took around three dozen spaceflights and 13 years to assemble the International Space Station. To be fair, a Mars mission won't require facilities as large and complex as the ISS, but the prevailing consensus at NASA still favors fewer flights.

"Humans are pretty needy," Lyles told me. "You're taking water, you're taking all of their environmental control systems, and whatever they need on a really long mission. A large, heavy launch vehicle is almost a no-brainer."

NASA is not alone in this conclusion. During a two-week span last month, private companies SpaceX and Blue Origin both unveiled giant, SLS-scale launchers that will become key parts of their future spaceflight aspirations.

An uncertain future

Back in February 2010, SLS didn't exist. As we learned in part three of our Horizon Goal series on NASA's human spaceflight program, that was the month the Obama administration's new budget and space strategy was released, which effectively canceled the agency's return-to-the-moon Constellation program.

Under Constellation, NASA was building two rockets named Ares I and Ares V, and a crew capsule called Orion. Ares I would have been a midrange rocket used to send Orion into Earth orbit, while Ares V was a heavy lift cargo hauler.

The White House's new plan extended the life of the International Space Station from 2016 to 2020. After the space shuttles retired, the job of ferrying cargo and crew to the ISS would eventually be outsourced to private companies like SpaceX. Until then, NASA would have to rely on its international partners—particularly, Russia—for ISS logistics. The venerable Soyuz spacecraft would soon become the only means of getting astronauts up and down from orbit.

The agency would funnel freed Constellation dollars into a new technology development program, with the goal of making future human spaceflight efforts more sustainable. That included a $3 billion, five-year investment on heavy lift rocket engine technology. 

But there was no plan or timeline for building a heavy lift rocket. That, combined with the fact that Ares I and Orion were out of the picture, meant there wasn't much hope for sending NASA astronauts beyond Earth orbit anytime soon.

From swamp to space

Uncertainty over NASA's future mixed badly with anxiety already brewing over the end of the 30-year space shuttle program. The unease was felt acutely in the southern U.S., where all five states ringing the Gulf of Mexico host NASA facilities involved in the agency's human spaceflight program.

Johnson Space Center in Texas is America's astronaut hub, and the home of Mission Control. Florida's Kennedy Space Center has launched every crewed American rocket since Alan Shepard's Mercury mission in 1961.

Equally important are NASA's Marshall Space Flight Center in Alabama, Stennis Space Center in southern Mississippi, and the Michoud Assembly Facility in New Orleans, Louisiana. This triad of facilities was used in the 1960s and 70s to design, test and build the Saturn V moon rockets, and the process was repeated throughout the space shuttle program.

Thus, southern Congressional representatives reacted strongly to the Obama administration's new plans. 

"The President's proposed NASA budget begins the death march for the future of US human space flight," proclaimed Alabama Sen. Richard Shelby at the time. "Congress cannot and will not sit back and watch … the destruction of our human spaceflight program."

"America's decades-long dominance of space will finally come to an end," warned Texas Sen. Kay Bailey Hutchison. 

"If the commercial boys don't work, then we are stuck for upwards of a decade relying on the Russians," said Florida Sen. Bill Nelson, referring to the plan to outsource ISS transportation to the private sector.

Shelby, Hutchinson and Nelson all held key space and financial committee positions in the Senate, giving them the legislative power to alter policies that affected their states. 

More broadly, there was Congressional resentment over the way the plan had been rolled out, according to Mary Lynne Dittmar, the executive director of the aerospace industry-led Coalition for Deep Exploration. The White House—due to either a political miscalculation, lack of time before the federal government's February budget deadline, or both—had not tested the waters to see how Capitol Hill would react.

"You just don't blindside Congress," Dittmar told me. "There were people on the Hill—people who don't really care about NASA—who were so angry about being blindsided, that they took up arms." 

Jim Kohlenberger, who was chief of staff for the White House Office of Science and Technology at the time, said that in retrospect, the administration probably should have done things differently.

"The one thing NASA hasn't invented is a time machine," he said. "If they did, I think we'd use it."

The president weighs in

Following a series of contentious congressional hearings, President Obama traveled to Cape Canaveral in April 2010 in an attempt to placate critics. First, he visited SpaceX's launch pad and met with CEO Elon Musk. Then, he took the stage at Kennedy Space Center's Operations and Checkout building, where a familiar, gumdrop-shaped capsule loomed over his left shoulder.

It was the Orion crew vehicle—axed with Constellation just two months earlier. Obama said the spacecraft would "be part of the technological foundation" for future deep space exploration missions, and also see double-duty as an ISS lifeboat.

Next, Obama gave his $3 billion, heavy lift rocket engine design effort a deadline: 2015. After that, NASA would start to build the rocket itself.

Thirdly, he gave NASA the deep space destinations it is still striving to reach today, one-upping his presidential predecessor with locations harder to reach than the moon.

"By 2025, we expect new spacecraft designed for long journeys to allow us to begin the first-ever crewed missions beyond the moon into deep space," he said. "We'll start by sending astronauts to an asteroid for the first time in history. By the mid-2030s, I believe we can send humans to orbit Mars and return them safely to Earth. And a landing on Mars will follow. And I expect to be around to see it."

Orion and a heavy lift rocket were back in play. Together, they would be used to send humans to an asteroid and Mars.

Your move, Congress

Like most legislative processes, crafting space policy is like playing a game of chess. There are moves and countermoves.

Because the White House proposes the federal budget, it always gets the opening move. Congress counters by passing bills that authorize programs and allocate funding. The President gets a final say with the ability to either sign or veto those bills.

After Obama's April policy speech, Congress began work on what would eventually become the NASA Authorization Act of 2010. As the name implies, the Act authorizes the agency's programs—which are proposed by the White House—while also setting spending limits. 

The bill went along with many of Obama's proposals, including outsourcing ISS transportation to private companies. 

There was, however, one major change: NASA would not spend five years researching heavy lift engine technology. Instead, it would begin building the rocket right away, using its current workforce and existing shuttle and Constellation technologies. When feasible, the agency was also directed to use or modify existing Constellation contracts, and both the rocket and Orion should be ready for test flights by the end of 2016.

The rocket was given a name: the Space Launch System, a nod to the Space Transportation System, the formal name of the space shuttle.

The Authorization Act is notorious for not only having created SLS, but for dictating design elements right down to payload capabilities: at least 70 tons for the initial version, and 130 after future upgrades.

The constraints left little wiggle room for a design resembling anything other than Ares V, which had been canceled with the Constellation program. Former NASA deputy administrator Lori Garver, who has openly criticized SLS since leaving the agency in 2013, says this was no coincidence.

"It ended up that the prime industry contractors got together with a few senior NASA and Capitol Hill people to modify the Ares V architecture just enough that they could keep all their existing contracts and change the name," she told me.

Behind the bill

Garver is hardly alone in her charges. SLS critics decry it as a pork-barrel project designed by legislators and the aerospace industry to keep government money and jobs flowing through traditional space districts.

But the alternative was not politically feasible, according to Jeff Bingham, one of two former senate staffers largely credited with drafting the authorization bill. Without a replacement program, the loss of both Constellation and the space shuttle represented a potentially devastating blow to some of NASA's southern centers, which impact their local economies by billions of dollars.

"You've got the pressure of the current workforce, and horror stories about peoples' life savings being sucked up because they no longer have a job, and no prospects of getting one because you're basically doing away with an industry," Bingham said.

An Ares V-style rocket, then, would solve certain political challenges while still providing the heavy lift vehicle NASA had sought for decades. But why does the law impose such detailed requirements for the vehicle, such as payload capabilities?

"The pushback was there, such that if we weren't very specific, [SLS opponents] would find a way to go in a different direction," he said.

I asked Garry Lyles, the SLS chief engineer, what he thought about those 70 and 130-ton payload numbers that Congress wrote into the law. He said it likely goes back to studies NASA had been conducting since the days of Magnum—and possibly earlier.

"We had been playing around with concepts for years that ranged anywhere from a 120 to 150-ton capability," Lyles said. "It wasn't surprising that something like 130 tons showed up."

Revealing a monster rocket

The NASA Authorization Act of 2010 passed the Senate unanimously and cleared the House by nearly a three-to-one margin. With the November midterm elections—during which Democrats would lose their majority in the House—less than a month away, President Obama signed the bill into law on October 11, 2010.

The first design of SLS, however, would not be announced for another 11 months. In the interim, Congress accused NASA of dithering, while NASA said they merely wanted to get the design right. The clash came to a head in July 2011, when the Senate science committee issued a subpoena ordering NASA to turn over a suite of SLS-related documents.

Lyles, along with current Marshall Space Flight Center director Todd May, who was the first SLS program manager, both told me engineers spent several months in 2010 and 2011 doing trade studies before settling on a vehicle design. Even the artist's renderings were still being finalized the day before the rocket's big reveal.

"We had been messing around with graphics, and it came in with an orange core stage," May told me, referring to the rust-colored insulation that covered the space shuttle's external fuel tank. 

"Our graphics guy said, 'What if you painted it white?' So he did one for me like that. And that night, Gerst [NASA associate administrator Bill Gerstenmaier] said, 'I need a picture of the rocket.' And he didn't say why, so I just told our graphics guy to send him a picture of the rocket, and he sent him the white one."

The next day, on September 14, 2011, a contingent of Congressional representatives—led by Senators Bill Nelson and Kay Bailey Hutchison—hosted a small press conference with NASA Administrator Charlie Bolden on Capitol Hill. 

Nelson took to the podium first.

"We're about to—the administrator of NASA, Charlie Bolden, is about to—announce the most powerful rocket in history," he said.

As Bolden watched from the sideline, Nelson's aides flipped over two large placards with SLS artist's concepts. 

It was a pearl-white rocket with black markings, evocative of the Saturn V. The core stage, powered by five space shuttle engines, was the size of an elongated shuttle fuel tank. A conical adapter sloped up to upper stage, which would be propelled by the J-2X engine that had already been in development for Ares I and Ares V. Two upgraded shuttle boosters were strapped to the sides. At the very top, under a protective shroud, was the Orion crew capsule.

The rocket's striking white paint job was such a hit, May said, that the SLS team began considering its possible benefits, including moisture protection.

Building SLS would take years of engineering ingenuity and political support. The rocket's predecessors, including Magnum and Ares V, never made it off the drawing board. Was NASA finally going to build its space shuttle-derived "monster rocket," as Senator Nelson dubbed it?

In part five of our Horizon Goal series, we'll find out.

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