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Jewish World Review June 21, 2001 / 30 Sivan, 5761
Bill Tammeus
http://www.jewishworldreview.com -- WHEN there's a baseball game on the radio -- and I'm not, say, performing brain surgery, rotating my tires or doing something else that requires engagement of the generally unused 98 percent of my gray matter -- I carry around my neck a small radio with headphones. It is not an expensive radio. In fact, I think it cost me less than a case of beer (this is how you measure baseball-related costs). But the radio works, and I am able to stumble through my life doing other things while also listening to broacasts of the national pastime, which I consider to be my patriotic duty -- along with voting against certain politicians. Well, I say I listen to the game -- and often I do. But if I turn my head just right, the reception sometimes goes all gnarly and erratic. At times the sound goes away altogether. Which is when I think about the amazing ability to receive radio signals enjoyed by the Deep Space Network of the National Aeronautics and Space Administration. (That's the difference between you and me, apparently. When you lose good radio reception of a baseball game, I bet you wonder what's happening in the game. When I lose it, I wonder about deep space. I don't say that to make you feel stupid. I say that, rather, to get all the way to this close-parenthesis mark.) The Deep Space Network, which from now on I'll call DSN so I don't have to suck up so much precious newspaper space, is a worldwide system for communicating with interplanetary spacecraft. The problem is that these spacecraft emit radio signals so faint that my own baseball radio would laugh at them. NASA has reported, in fact, that "the total signal power arriving at the network antenna from a spacecraft transmitting from the outer solar system is 200 million times weaker than the power level from a modern digital watch battery." It impresses the very devil out of me that NASA has employees with so much time on their hands (digital time, no doubt) that they can fool around and come up with statistics like that. But NASA's possible overstaffing isn't my focus here today, so we're going to slide by that subject. Rather, I want you to know that the DSN is gearing up for a veritable traffic jam of radio signals that, starting in a couple of years, will flood back to earth from spacecraft being aimed hither and yon in the cosmos. There now are three batches of antenna designed to pick up radio signals from deep space. One is in California, one in Spain and one in Australia. Each one includes a gigantic 230-foot-diameter antenna that can track spacecraft more than 10 billion miles from Earth. If you travel 10 billion miles into space in a reasonably straight line (remembering that space is curved), you're not going to make it back for lunch. Or even dinner. Or maybe even for the end of the Cheney administration. Earlier this year, for example, the DSN picked up a radio signal from NASA's Pioneer 10 spacecraft, which was out beyond Pluto. This radio signal registered just a billionth of a trillionth of a watt. It was almost as weak as Jenna and Barbara Bush's excuse for underage drinking. The DSN is being upgraded so that the system will be able to pick up more radio signals from a bunch more spacecraft that will be heaved up (a relative sort of direction) into space -- or already are there.
"We're getting ready for a crunch period beginning in November
2003," says Rich Miller of NASA's Jet Propulsion Laboratory. I'll
upgrade my radio then, too, in celebration of the just-ended 2003
Cubs-Royals World
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