Sunday, April 13, 2014

Economizing Orbit

It's a good time to be in the private spaceflight industry. With NASA increasingly retreating into the background, companies like SpaceX, Planetary Resources, and Virgin Galactic are moving forward to make new forays into spaceflight, both on government contracts and for private ventures. While NASA has increasingly lost its way, private companies founded by far-reaching individuals exhibit a mix of idealism and market-oriented pragmatism that may (fingers crossed) be the key to turning spaceflight into a far more attainable, and affordable, reality.

The first SpaceX Dragon spacecraft launched into orbit, photographed during a tour of SpaceX's headquarters I was fortunate enough to go on two years ago.

The hardest part of getting to space really is the first hundred kilometers--the immediate pull of Earth's gravity is far and away the biggest obstacle, and so the amount of energy you must expend decreases as it does, according to an inverse-square law. Thus, an economic means of reaching orbit has long been the holy grail of spaceflight agencies. NASA hoped that they had hit on it when, in 1981, they first launched a reusable spacecraft meant to reach orbit for a fraction of the cost of the disposable Mercury, Gemini, and Apollo spacecraft that had preceded it. NASA was so optimistic that this would be the future of affordable spaceflight that they named the program the "Space Transportation System," as if it were a quick, cheap bus from Florida to low Earth orbit. They hoped to be able to launch it as frequently as once per week, for as little as \$20 million per launch.

However, the Space Shuttle never launched more than nine times in one year, and distributing the \$209 billion sunk into the program over its 135 flights yields a cost of over \$1.5 billion per flight, not to mention the lives of fourteen astronauts in what were likely preventable disasters. It is hard to argue that in its primary mission--being affordable, reliable, and frequently reusable--the Space Shuttle was a complete and utter failure.

The launch of STS-107, the final flight of Columbia. A piece of foam that broke off during this launch damaged the heat shield on the left wing, ultimately leading to the orbiter disintegrating on reentry and killing its crew (source).

The overwhelming cost of the Space Shuttle program, along with the catalyst that was the Columbia disaster of 2003, ultimately led to its cancellation in 2011--nevertheless, this was fifteen years after the program was planned to come to an end. A combination of politics and the unending delays of the International Space Station, along with unwillingness on the part of the US Government to fund new spacecraft, kept the ailing program alive far past when it should have been ended. Now, however, NASA has abdicated its role as the driving force behind American manned spaceflight, vague ideas for using the cancelled-but-revived Orion spacecraft to orbit the Moon or visit an asteroid notwithstanding. And that may be the best thing that those of us hoping to see real progress in sending humans into space could hope for.

An artist's impression of the Orion spacecraft, which might someday exist as more than a check written to Florida voters (source).

While NASA has been foundering in its search for purpose, private companies have been getting creative, funding ideas that likely never would have made it through congressional review. After it took the US, ESA, and Roscosmos nearly 20 years to launch the 500,000-kg International Space Station into orbit, part by part, Bigelow Aerospace began work on cheap and (most importantly) lightweight inflatable space station modules. SpaceX, which is sending its third Dragon resupply mission to the ISS this week (knock on wood), is using the mission to test prototype systems for a fully reusable rocket capable of landing vertically after sending its upper stages into low Earth orbit. Members of Congress, and the voters behind them, have long been skeptical of the financial value of funding spaceflight (despite the fact that the money that the US has invested in NASA, all of its mismanagement notwithstanding, has almost likely been returned several times over). But that financial value may be what saves human spaceflight, by motivating and rewarding private investment by companies willing to take the risks that NASA isn't.

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