Friday, July 8, 2011

Farewell to the Shuttle

Today the space shuttle launched on its 135th and final mission.  When the four astronaut crew of Atlantis arrive back on Earth just two weeks from now, a complicated chapter in human spaceflight will draw to a close, and then, for better or for worse, we will have plenty of time to ponder its place in history.

For the next several years, American astronauts will have to hitch a ride aboard Russian Soyuz rockets to visit the space station largely funded by US taxpayers.  In just two weeks, Russia will become the only nation on Earth in the business of launching humans into space on a regular basis.  But after a few more years, hopefully, Americans will be flying into orbit atop commercial spacecraft, and NASA will be well on its way toward the goal of sending human beings far beyond low-Earth orbit, to an asteroid, and eventually to Mars and its moons.

But the future of manned spaceflight is by no means written, and the legacy of the space shuttle's successes and shortcomings looms large.  Conceived during the Apollo era, finally launched for the first time in 1981, the space shuttle never quite lived up to its promise of routine spaceflight.  It was a technological triumph -- an elegant, reusable space plane capable of delivering large payloads and even retrieving spacecraft to bring back to Earth.  But in a way, the seemingly unadventurous nature of its work sapped the energy out of America's appetite for space exploration.  The higher-than-expected costs, and the tragic loss of two crews in 1986 and 2003, made us question whether the whole endeavor was really worth it.  Even as the shuttle's unique capabilities allowed us to service the Hubble Space Telescope five times in Earth orbit, and delivered many sections of the now magnificent International Space Station, the shuttle program came to be seen by many observers as a waste of time, a holding pattern of sorts.  We had made some daring ventures into the abyss, landing 12 men on the Moon, and then we spent 30 years orbiting the Earth, again and again and again and again.

To say that flying the shuttle was not a daring enterprise is a step too far.  Spaceflight of any kind is an extraordinarily complicated venture, where the slightest malfunction can result in catastrophic failure.  The Challenger and Columbia disasters are a testament to the true hazards of human spaceflight.  But with the advent of the shuttle program, NASA's mission slowly diverged from the dreams of its financiers, and in failing to hold the imagination of the public, what was arguably the main driving force behind human spaceflight -- the itching desire to explore the frontiers first hand -- withered with each successive flight.

By and large, in the 1960s America was not terribly interested in geological discoveries on the Moon.  The Apollo program was not really about science, and for most people, the science was probably of tertiary concern.  Politically it was about beating the Soviets, for sport and for security, but viscerally, we recognized its deeper meaning.  To walk on the Moon, that rock that has circled serenely above us for billions of years, never once lighted upon by creatures from the Earth, was truly a moment for the ages.  Never again would it be an untouched world, forever would it bear the footprints of humans.  It was arguably the crowning achievement of human technology.  But after only 6 successful landings, we pulled back to plan our next move.  The Russians were working on space stations, so we had to get into that game, too.  In a sense, the very thing that had driven us to such great heights in the age of Apollo  -- competition with the Russians -- drew us back to spend the next three and half decades orbiting the Earth.  Meanwhile, dreams of a rapid expansion of space exploration, with moon bases and Mars landings, largely evaporated.

Still, the space shuttle was and is the greatest vehicle ever built for low-Earth orbit operations.  But perhaps it was always doomed to live in the shadow of Apollo.  The splendid optimism of space exploration in the 1960s, the breathtaking speed at which we achieved our goals, the seemingly limitless possibilities, gave way to the static pessimism and cutbacks of the 1970s and 1980s.  Perhaps Apollo was just the high that we could never hope to achieve again.

In spite of all this, I will miss the space shuttle.  It has served us well, and the 355 brave astronauts who have flown on the shuttle have done important work -- conducting a host a valuable zero-gravity experiments, launching interplanetary spacecraft, repairing satellites, and ushering in a new age of international cooperation in space with the Mir and ISS programs.  But the shuttle's retirement is a necessary part of moving on to the next mission.  If there is something to lament, it should not be the end of a program that by any standard has gone on a bit too long; rather, it is the wide gap between STS-135 and the launch of the next manned American space vehicle.  That remains four or five years away, and the way forward is a little murky.  Funding for manned space flight is in limbo, though it always seems to be.  But as Congress wrestles with the White House over the money and the mission, we will cool our heels while Russia takes our astronauts up at $63 million a ride.  Perhaps we will feel the itch again in the meantime.

The so-called Commercial Crew program seems to be the right way forward.  If we are to make manned orbital flights truly routine, as we should hope they will be one day, commercial operations are the next logical step.  The resources at NASA are to be refocused on missions beyond the Moon, to an asteroid in 2025 and to Mars in 2035.  There's good reason to suspect those dates may slip, as firm deadlines don't seem to mean quite as much as they did in the 1960s.  We have set our sights on new horizons, but it will take sustained effort to meet those goals.  Spending the next four or five years languishing without a manned space program of our own may frustrate the public just enough to renew our desire to explore.

At first glance, the time frames involved with going to an asteroid and eventually Mars may seem terribly timid.  But we should not forget that going to an asteroid, let alone Mars, will be a spectacularly difficult exercise, for which we are just beginning to design serious plans.  The Mars landing, recently described by The Economist as the "El Dorado of space exploration," will require preparation and design of unprecedented sophistication.  We have not yet even managed a robotic sample return mission from Mars.  Sending astronauts across the interplanetary gulf separating Earth and Mars will be far more dangerous than crossing the mere quarter-million miles from the Earth to the Moon.  In fairness to NASA and the shuttle program, dreams of a Mars landing very shortly after Apollo were probably far too optimistic.

So, here we are.  Will we press on to greater voyages, sending out at long last our cosmic argonauts to plumb the depths of interplanetary space?  Or will we wait for the next generation to pick up the mantle we have borne just a little way from where we started?

Time will tell.  In the meantime, we say farewell to the space shuttle.  Good luck, Atlantis.