I am sure that today, just as you could 18 years ago, if you were to ask a group of children what three things they might want to be when they grow up, you'd hear "an astronaut" from the vast majority of them -- if not all. It's the kind of dream adventure -- because these second-graders, these 7- and 8-year-olds, don't look at it as a job yet -- everyone considers at some point, in some way. So many may think of it, but only a select few ever make it there.

I am sure this is the answer you would get from today's children, those who were born long after our last tragedy in space flight -- the Challenger on Jan. 28, 1986. But would I be right? Do today's children still dream of blasting off, of attending Space Camp, of floating in space? I was not yet 10 years old when the principal of Point Road School came on the intercom that morning and, with only a few words I didn't even catch, put the microphone up to the radio. It was a very confusing moment, and the first words I heard were "Atlantic Ocean," and something in me told me that it was not good. Something else told me it was the space shuttle.

That was my first "Where were you when ..." moment and I'd never had anything to compare it to, no experience to draw from. Yet I still sensed that a tragedy had befallen Challenger and its crew of seven -- yes, the same number as the crew aboard Columbia yesterday. I had been aware of the shuttle blasting off that morning, so when I heard "Atlantic Ocean," I just knew. We were sent back to our home rooms and the teachers brought in TVs and turned on the news for us. It was a great learning experience, being able to watch live and learn as we grew.

I loved watching shuttle liftoffs as a kid. It upset me when they'd be scheduled for a time before school but various minor delays would push it back to a time after I'd have to leave the house, and I'd miss it. These were the days before a VCR in every house -- yes, there was such a time -- and there was no way to watch it unless you watched it live. News coverage didn't do it the justice it deserved -- or I craved -- and besides, I was a kid: I didn't watch the news.

Had space flight become routine by 1986? Had we lost interest in it? I don't know; that's something I couldn't gauge back then. But after Challenger, NASA put space flight on hold to figure out what went wrong. When they resumed in the 90s, it must have gotten good coverage, but I didn't notice.

The last -- and only -- liftoff I've seen live since before Challenger was on Oct. 29, 1998, when John Glenn flew aboard Discovery and I watched with a lump in my throat. Since then, though, NASA's missions have gone unnoticed by most of us, myself included. Occassionally I'd check the web site to see when the shuttle would be flying and if I'd be in Florida -- or could plan a trip -- to someday watch a liftoff live. A few weeks ago, I checked to see if something might be happening when Casey and I go to Orlando in two weeks, but knowing that Columbia was already up there, I knew it was not likely. Sure enough, the launch schedule said the next one was not to happen before March 1.

Now, who knows?

Discovery is a trait of human nature. We travel because we're curious; we're intrigued by what lies beyond. We're spurred on when told we can't attain something; we're encouraged by not having something. While many of us work in stores and cities and buildings and on farms, a few of us work in and above the atmosphere, with the help of so many on the ground. While some worked in markets and churches, Columbus set out for India more than 500 years ago. While Americans lived in cities clustered along the Atlantic Coast and along rivers reachable by sea-faring vessels, Thomas Jefferson sent Lewis and Clark west from St. Louis 200 years ago to find out what was in that piece of land he'd acquired.

When Russia shot Yuri Gagarin into space in 1961, President Kennedy vowed to land a man on the moon. With the Cold War heightening the sense of competition between the two countries, the U.S.S.R. and the U.S.A. found a way to conquer the darkness beyond our atmosphere. Today, the two countries work together to figure out how we're going to get the three residents of the International Space Station -- two Americans and a Russian -- home. That March 1 shuttle flight was to have replaced the crew.

But just as various tragedies have failed to bring an end to space exploration, I doubt the crumbling of Columbia will prove to be the end. There is still too much we want to know, too much we want to explore for this to hold us down. Because space flight is unique and rare, many of its missions are overlooked; it is only the extraordinary -- and, unfortunately, the tragic -- that grasp this much attention. But how many other jobs bear such great risk? There must be some, no? From this we will learn, and continue.

I cannot tell you what good the space program is for, and I cannot defend it with facts and evidence. However, I also can't tell you the purpose of hundreds of other endeavors, and from those we may someday find a cure for cancer or clean the environment. I can only trust those who are trained and paid to know those things, to study those things and make those decisions. I am sure space flight still has an important role to play, and I know there are still enough brave men and women willing to take the necessary risks.

Whenever I fly, I like having a window seat to look down on the world from 30,000 feet. A rush comes over me when I can distinguish rivers and shorelines to the point where I know it's the Mississippi or Virginia. I've seen the pictures from space, the view of the Earth from far above. I wonder if anyone can behold that in person and still doubt the existence of some sort of god.

I'm not much of an adventurist -- or a churchgoer -- myself. I read Outside and other magazines and become wrapped up in the exciting travels of others, but I don't know how close I'll come to most of them. If I were given the opportunity to fly into space, though, I know this much:

I wouldn't say "no" right away.