I see in this morning’s Reno, NV paper that Nevada is on the list as a possible test/launch site for Lockheed Martin’s VentureStar spaceplane (the old NV Test Site down by Las Vegas–Area 51, here we come!). Our governor, Kenny Guinn, is hot on the idea, but is quoted as saying “Our launch pad would be a mile up (in elevation) already, and the first mile is the most expensive” for launch. It’s too soon for me to judge Kenny as a governor–he came into office in January–but I thinks his physics is (are?) a little suspect. As I understand it, the cost of the first mile or so is due to the fact that the vehicle has to generate enough thrust to get its weight and the weight of the neccessary fuel to orbital velocity. As speed increases, mass decreases as the fuel burns. I can’t see that one vertical mile, and, I suppose, the lower air pressure, would make that much difference. Any comments? It’s been fun seeing some practical discussion of orbital mechanics around here lately, especially considering some of the off-the-wall scenarios they’ve started from!