Back to the Future

This week, NASA launched the Orion spacecraft on a test flight. I have a conflicted viewpoint about this event. To me, Orion is both exciting and deeply disappointing.

On the one hand, Orion is NASA’s first entirely new spacecraft for human crews in over twenty years. There have been only seven in American history: Mercury (first successful flight in 1959), Gemini (1964), Apollo (1966), Skylab (1973), Space Shuttle (1981), Space Station (1992), and Orion (2014). Those dates have been getting unacceptably distant from one another, and it is wonderful to see NASA getting its game back on. Test flights are NASA’s business. The agency is supposed to operate in the proving ground of technology. I want to see it doing new things, and the Orion flight was a reasonable first step towards NASA getting back to its roots. Those roots, after all, were triumphant!

On the other hand, though, Orion falls far short of what NASA could, and should, do. The spacecraft is an improvement over the last capsule NASA designed – the Apollo Command Module – but it is an incremental improvement rather than a revolutionary one. As an example, one of the technological advancements NASA has been touting about Orion is its glass cockpit. But this is the era of the iPad: in such a mass- and volume-constrained environment as a space capsule, the glass cockpit is simply not innovative – it is obvious. (For examples of innovation in space vehicles, try inflatable habitatsrockets that fly back to their landing pads or crew shuttles that could land at any normal-sized airport runway.) To make matters worse, not only is Orion an incremental step in capability from the early ’70s, but its development is horrendously stretched. For reasons that are political, programmatic, and cultural, rather than technical, the next flight of Orion will be in 2018. A human crew will not use the capsule until after 2021, at which point it will be almost a decade old itself.

I think the most bitter disappointment is the concept of what Orion will do when it finally does have astronauts on board. The current plan is to build the world’s biggest rocket, the Space Launch System, and use it to send an Orion crew to asteroids and Mars. I’m all for visiting those places, but the “giant rocket with space capsule” architecture – the architecture of Apollo – is a recipe for one-shot visits to other worlds. After the first astronauts return from such “flags and footprints” missions, there is a very strong risk of program cancellation. I don’t want to see our space program cancelled.

An Orion capsule riding a Space Launch System rocket is not even close to how I would design a sustainable, long-term space program. A much better approach is to use many different spacecraft, and specialize them for individual purposes. Think of the Apollo Lunar Module: it was a flimsy, silly-looking vehicle that was exactly suited for the prospect of landing and taking off from the Moon’s surface. Instead of building on Apollo and Space Shuttle heritage to make an “all-purpose” space capsule, I would like to see NASA lean on its Space Station experience to design a set of interplanetary transport spacecraft. These vehicles would stay in space for their whole lives: we would assemble them in space, launch them out of Earth orbit rather than from Earth’s surface, and we’d never use them to carry astronauts up from and down to the ground. Whenever they need more fuel, we’d send only the fuel up to them – not a whole new vehicle. When we need to rotate astronaut crews, we could always hire SpaceX.

That sort of multi-vehicle concept offers some big advantages. First of all, it’s much more flexible than giant, infrequent, one-shot missions. Second, it’s far more efficient and cost-effective. Think about this: 20% of Orion’s mass is its heat shield, a component only needed for the last ten minutes of its mission. If Orion is returning from Mars, then that means our Mars return rocket needs to be huge in order to push that heavy heat shield on its half-year-long journey back to Earth. And if the heat shield and Mars return rocket need to be huge, then the Earth departure rocket needs to be enormous. Instead, though, we could forget sending the heat shield to Mars in the first place. Forget having the vehicle that goes to Mars also be responsible for landing on Earth. When the astronauts come back from Mars, you just send a little rocket with a little capsule into Earth orbit – just enough to bring the astronauts to the ground. The lightweight interplanetary spacecraft stays in space.

In 2011, when Congress ordered NASA to begin work on the Space Launch System, internal NASA studies came out that agree with my assessment. Multi-vehicle approaches that we can re-fuel and re-use in space are more efficient and cheaper than SLS. They will also get astronauts to other worlds much sooner. Most importantly, such approaches won’t be reliant on one-and-done missions. They will be much more likely to keep our explorers in space.

That is why, while I applaud NASA’s successful demonstration of the ability to launch new vehicles, I hope the agency moves on quickly from Orion, and begins work on a new fleet of exploration vehicles to stay in space.

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