Risa and I are sitting right next to the countdown clock. The shuttle is waiting patiently about three miles away. It is fueled up, and ready to go. In the last 15 minutes the sky went from completely overcast to patchy sun to brilliant blue sky with a few puffy clouds. We are now 2:58:22 from launch.

To be honest, I’m surprised by how excited I am. Yesterday we toured the facilities at Kennedy Space Center, and got to see the shuttle up close. It is impressive. Of course, it’s huge. But it’s hard to wrap one’s mind around the simple essential fact: this object is going into space! However, there’s something more primal about all this. I think every kid growing up since the 60s (and presumably well before?) must have had an “obsession with rockets” phase. What could possibly be cooler? They are huge. They go really, really, really fast. They make loud noises. They go exotic places. They are the perfect vehicles for a child’s imagination. As we grow up, most of us lose our fixation. But, as I’ve found out in the last 24 hours, it hasn’t been lost, only misplaced. When you actually see a rocket about to head into space, it’s a completely overwhelming experience. All those emotions come roaring back, and you’re left mesmerized and excited and giddy, just like you were as a 10 year old.

We just took a little break and walked down to wave to the astronauts. They are in the astrovan, an (entirely appropriate, completely antiquated) airstream motorhome. They stopped briefly to say goodbye. Their next stop is the shuttle (and then 300 km up). You might think that this is just part of a media stunt, a final wave for the cameras. But, at the end of the day, these six individuals are about to strap themselves to the top of 1.2 million kg of liquid oxygen/hydrogen (by my calculations, the equivalent of 0.7 kilotons of TNT—a “small” nuclear bomb). This is not all just fun and games; it is a deadly serious enterprise.

We are now 1:53:33 from launch.

There are more photos/real-time updates at our twitter feed, and even more information at the NASA tweetup page.