Saturday, July 26, 2008

"we would have been on Mars 15 or 20 years ago"

I've long been fascinated by space exploration and it was with considerable interest that I read NASA Director Michael Griffin's interview with the Guardian. Britain has been such a no show when it comes to space I find it odd that a British paper should interview him, but I disgress. It would be equally digressive to discuss Griffin's controversial (to say the least) airing of his doubts about global warming. So let me just call attention to Griffin's remarks about the missed opportunity of the 1970s:

In the vacuum that followed the Apollo programme, Griffin says America squandered a unique chance to push on to other planets. The error, he believes, was the Nixon administration's decision to focus on sending astronauts into orbit around the Earth.
"Working in low Earth orbit was not bad. Working exclusively in low Earth orbit was bad," [Griffin] says. "I spent some time analysing what we could have done had we used the budgets we received to explore the capabilities inherent in the Apollo hardware after it was built. The short answer is we would have been on Mars 15 or 20 years ago, instead of circling endlessly in low Earth orbit."

Many observers have questioned why manned space exploration dried up like it did after Apollo. I had concluded that it was because direct missions (i.e. missions that did not involve on-orbit assembly) would always be limited in their capabilities such that to really open the door to space, one had to concentrate on minimizing the cost of throwing stuff up to LEO. Achieve the technological breakthrough that gets us through the gravity well, and we're away. But then we found that the shuttle could never be run cheaply. Whatever the theory concerning the potential for a (partially) reusable launch vehicle, each launch required an enormous ground army of workers; the airline-like operations once envisaged were never realized.

Reusable SSTO was supposed to be the ticket. But reusable SSTO ultimately couldn't overcome the engineering challenges, which were extremely daunting in any case since the margins for feasibility were already very thin in theory. The death of the X-33 project meant that, in essence, we could not innovate our way into space, at least not in our lifetimes.

If you can't innovate your way into lower costs, your only other option is the economy of scale approach. Go back to the big dumb Apollo system. And, indeed, that appears to be what has happened, with the phasing out of the Shuttle in 2010 and the development of the Apollo-like Orion system.

Griffen's comments underline the contention that both Shuttle and the Space Station were essentially enormous boondoggles that delayed a human voyage to Mars by decades relative to an extrapolation of Apollo systems beginning in the 70s. Either that, or Shuttle and Space Station were necessary diversions that proved that manned space flight is simply too difficult or expensive to make any rational sense, the resulting inference being that robotic exploration is the way to go.

As an aside, I can't help but wonder at Griffen's seven degrees... I'd thought I'd gone a bit overboard with just four! I have to agree with him about global warming, in any case:
I have no doubt that ... a trend of global warming exists. I am not sure that ... it is a problem we must wrestle with. To assume that it is a problem is to assume that the state of earth's climate today is the optimal climate, the best climate that we could have or ever have had and that we need to take steps to make sure that it doesn't change.

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