17,500 mph

I just watched the Discovery embark on its 36th mission. It was like watching some great fire-breathing dragon go from 0-17,500 mph in four minutes, a cosmic dragster hurtling toward space. When those three main engines start up they generate a thrust of over 6,000,000 pounds, a net 1,500,000 pounds over the enormous weight of the shuttle and its accompanying two solid rocket boosters and external fuel tank. By comparison, it would take 600 jet airliner engines to produce the same amount of thrust.

In elementary school, we were in the heat of the space race. There were always articles in our weekly reader that had something to do with space or space travel. I remember such mundane facts such as the mass of the moon is one sixth that of Earth so that we would only weigh one sixth of what we weigh on earth. However, we would still have the same mass thus the same inertia. (Actually, this last little tidbit of knowledge came later in my reading, probably from one of Robert Heinlein's science fiction novels. I can easily say that I learned a large amount of what I know about physics from science fiction, not to say that I'm a rocket scientist.)

The escape velocity of Earth is 25,000 mph or 7 miles per second. My dad used to drive us to have dinner in Waldorf, Maryland back then. I used to look out the window up at the stars, gaze at the Milky Way and used to think that if we were moving at 7 mi./sec. we could make it home in 5 seconds, and that was a 35 mile trip... but it always took us the better part of an hour. Somewhere in my database was the fact that the Milky Way was what we saw of our galaxy from Earth and the stars just distant suns like our own. Of course, now I know that very few stars are suns are like our own, but rather any number of star types such as white dwarfs or red giants.

Getting back to the space shuttle, one would expect to feel the force of three gravities during liftoff. This is the same amount of g-forces that a funny car produces at maximum acceleration. When we're on a roller coaster we feel negative g-forces as we go down a slope and positive g-forces as we climb one. The earlier Apollo-era Saturn 5 rockets produced something like six g.'s during liftoff. That would be like going from 0 to 100 mph in less than a second, enough to make you pass out if you weren't in top shape.

If we held out long enough on our Apollo trip, we would be rewarded with the near zero gravity of Earth orbit, or punished depending on your fortitude for the sensation of falling. Zero gravity is what we feel as we fall, as if we went straight down on our roller coaster ride. It tends to take your stomach away and its contents with it, or at least it does me. NASA has through its history used any number of aircraft that performed a kind of aerial roller coaster ride so that its occupants experienced zero gravity. These aircraft have unofficially been known as "vomit comets" due to their unpleasant side effects.

Getting back to this evening's launch, I watched with anticipation and morbid dread as Discovery approached one minute and 13 seconds into launch as that was the amount of time into Challenger's flight when it exploded in 1985. It's not well known that the crew did not perish in the explosion, but rather died from impact when the spacecraft slammed into the sea after falling for so many miles. I happened to mention that to someone in casual conversation and then they asked me how I knew that. I replied that it was from a History Channel piece. The reason the person wanted to know was because they worked for NASA, and it was not considered common knowledge. Sometimes I think about what they felt as they fell to their deaths. They no doubt knew that they were going to die. And as the shuttle program nears its end over 20 years after, if the same thing happened again, the outcome would be the same. There are no escape hatches or parachutes.

But such is the cost of space exploration (and space exploitation). Without human sacrifice where would any of us be? It's truly amazing to me that not more lives have been lost in the space program, and more than one NASA employee has told me that it amazes them every time a shuttle successfully launches, there are so many things that can go wrong. Now satellites are banging into each other there so many of them, and next we will have to be renting out space in outer space or at least allocating it. And so I wonder will we ever go back to the moon and perhaps start a colony, or is next stop Mars and beyond? I hope both.