Monday, April 21, 2008
Lil Hucky, the little Clowncars and I ventured out at sunset to watch this month's full moon (called the pink moon, Hux tells me, named after trees that bloom pink blossoms this time of year). We do this fairly often. It was cloudy, so the moon was less than spectacular, but I learned a little trick. We always park in the same spot to watch moonrise, and we always guess where on the horizon it will come up (the person with the closest guess "wins"). And while we were sitting there in the car, an extremely simple way to predict where the moon will rise occurred to me: look where your shadow is pointing! That is where the moon will rise. Cool, eh? And so simple. This'll only work for a full moon (as the sun and the moon are only directly opposite each other then), but, at least this time, it worked like a charm. My obsessive interest in orbital mechanics pays off!
Sadly, I told my family immediately upon figuring it out and thus cannot use my newly-gotten knowledge to win the moonrise guessing game. I can only use my powers for good, not evil. I'm like Gamera!
In other news, I found an answer to the baseball-thrown-from-the-space-shuttle question at the Straight Dope. Not an unimpeachable source, but a pretty good one. And amusing to boot. According to them, throwing the baseball toward Earth, or away from Earth, will not affect the orbit of the baseball at all. As Larry Niven (a GREAT sci-fi writer) puts it, "East takes you out, out takes you west, west takes you in, and in takes you east." Orbits depend upon speed. If you don't change the speed of the baseball, you won't change the orbit.
So, the only way to change the orbit of the ball so that it'll fall to earth is to throw it straight back from the shuttle, to slow it down. But (and the math here is seriously over my head, so I'm trusting the Straight Dope) a ball thrown at 92 mph wouldn't come close to getting it out of orbit - you'd be able to drop the orbit a 100 miles or so, but not all the way to Earth.
Atmospheric friction would eventually bring it down. But our premise here is a crowd at Yankee Stadium waiting for the ball to fall so the ump can shout "Play Ball!" And unless the crowd is willing to wait a few years, it's not gonna happen. Those Yankee fans are a notoriously impatient lot.