You all are area of the 2-hour, commercial-free telethon called "America: A Tribute to the Heros" airing tonight on virtually every network in the U.S. from 9-11 p.m. tonight (Friday), right? There's going to be a galaxy of stars on the program, including Stevie Wonder, Neil Young, Bruce Springsteen, Sheryl Crow, Paul Simon, Tom Petty and Alicia Keyes. It should rock. Some movie/televison stars are going to be manning/womaning the phones, so if you call in a pledge, you might get to speak to, like, Clint Eastwood or Julia Roberts! Speaking of stars, tonight marks the Autumnal Equinox, which is a pretty cool phenomenon, I think! You see, if you photograph the position of the sun in the sky at the same time every day, over the course of a year it would trace out a figure-eight in the sky. Why does this happen, you ask? The Earth is tilted on its axis 23.5 degrees in relation to the plane of its orbit around the sun. OK, great. But if that's all that was happening, the path traced out in the sky would just move back and forth along a straight line. So something else is going on: the Earth doesn't orbit the sun in a circle... but in an ellipse. When you sum these two motions together over a year, you get what's known as an an "analemma." The effect has been understood for a couple of thousand years (analemmas are inscribed on almost every schoolhouse globe), but because of the time involved and the delicacy of the long-term exposure, only a handful of photographs have ever been successfully captured. You might have guessed by now that the vernal and autumnal equinoxes occur at the crossing-point of the figure eight. Just thought I'd go celestial on you... Have a great weekend, my dear JMDL. -Julius
