Okay, you've probably seen film or video footag on TV. But if you haven't been to a launch, at least as close as the thousands of cars stacked up back out on the highway, you just don't know anything about it.

At first the world is nothing but horizon, endless ocean and sky, all of it still, tranquil, serene. Three-hundred-and-sixty-degree Spielberg, rich and vivid. Lazy clouds overhead, a flight of birds just visible gliding low over marsh flats in the distance, a few boats out on the water. The stillness is not perfect - there is the countdown bellowing out of those superb speaker horns, and there is the internal thunder of elevated pulse - but basically the world is as it has always been: at rest, indifferent to anything any of the scurrying ants on its surface might come up with.

Then Hell breaks loose.

A dirty white explosion spreads in all directions. At its center, beneath the stacked array, a Beast is born. It is mighty. And angry. Its roar shatters the world, splits the sky, echoes up and down the Florida coast and miles out to sea. You thought you knew what to expect, but this is louder. The sound is tangible, hits you with physical force, vibrates up your legs from the ground beneath your feet, scares the living shit out of you. Your first thought is that you are witnessing a disaster even more awful than Challenger: an on-the-pad explosion.

Then the Beast's two big brothers wake up - the giant solid rocket boosters - and Heaven, Hell, Purgatory, and Limbo all break loose together and start to argue. The sound is indescribable, just short of unbearable. So insensate is the rage of this new Beast that the world itself will not have it. No matter that something the size and weight of an apartment building is sitting on its back: it lifts from the ground on a raving column of its own fury and rises impossibly into the air, becomes a thick growing tower of white smoke, the 128-ton Shuttle stack balanced on top like a Ping-Pong ball on the stream from a fire hose. The bonds of Earth can be as surly as they like: the Beast is surlier, shrugs its terrible shoulders, and slips them clean.

You realize that you are pounding your hands together and screaming 'Go, baby, go!' like an idiot at the top of your lungs, and you gather that everyone around you is doing the same, but you can't hear any of it. Part of you wishes you had control of your hands so that you could take photos like you planned to, and another part is amused at the audacity of the notion that this literally earthshaking event could possibly be squeezed through a pinhole and captured on a piece of celluloid smaller than a matchbook. Instead you watch in reverent terror as a utensil built by bald apes flings ninety-seven tons of metal and plastic two million miles.

With five live men aboard.

You can read about something like that, and see it on television, and spend a large portion of your leisure hours trying to imagine what it must be like and thinking about what it means, and you think you get it. You're a space buff: if anybody gets it, you do. And I suppose you do - as an intellectual concept. Then you go there and see it with your own eyes, feel it with your own bones . . . and are astonished to discover that only now, for the first time, do you really Get It. Until now space travel had been real to me in the same sense that World War II was real to me, or China: I'd been told about it and had no reason to doubt what I'd been told. Now I got it.

For two million years it had been only a fantasy, a monkey dream. For the first fifteen years of my own life it had still been only a fantasy, something a teacher or a scientist might laugh at you for believing in. For the next quarter century it had been a news story - one that seemed to bore most of my fellow citizens silly. But now it was reality - real reality; that is, the part experienced by me - and the two-million-year-old dream had really come true:

The species I belonged to had figured out how to climb the biggest tree there is. We were already becoming familiar with its lowest branches.

In that moment, I knew, as fact, with utter certainty, that one day we were going to climb all the way to the top. Nothing was going to prevent us. Not presidents, proxmires, press, public opinion, economic forces, or nuclear winter.

No, it could be delayed, but it could not be stopped. This was evolution in action, before my eyes. As surely as we had come down out of the trees, as surely as we had crawled up out of the tidal pools in the first place, we were going to do this thing.

Spider Robinson - Callahan's Key