Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, May 27, 1993 TAG: 9305260256
SECTION: EXTRA PAGE: 8 EDITION: METRO
SOURCE: Joel Achenbach
DATELINE: LENGTH: Long
A: Look at Jupiter some night. Most brilliant! And Venus is so bright it is sometimes mistaken for a UFO. At least that's what we've read. The Why staff would never make that mistake, of course, because we're so sophisticated - if we ever saw a giant rotating saucer beam a pickup truck off a remote country road we'd probably say, "Hey, lookit that! Venus!"
It is worth noting that extrasolar planets might not even exist. But the planetary community presumes they do, and figures they're fairly common.
The official (that is, wrong) reason you can't see any planets around other stars is that the stars are too bright, relative to planets. The truth is that our telescopes are simply not good enough.
Stars are far brighter than planets (stars generate light and planets only reflect it). To get a measure of the difference you need only compare Venus or Jupiter to the sun. You can't even look at the sun, it's so bright. But if there were a big, fat, Jupiter-sized planet orbiting a nearby star, it would reflect enough light to be seen in a sensitive telescope if the image were not washed out by the light coming from the star.
"There are enough photons coming from a planet for it to be detectable," says Eugene Levy, a planetary scientist at the University of Arizona. But the planetlight is buried by starlight. Starlight is splashy, it scatters within the telescope itself, and appears as a smudge rather than a nice, neat point.
Levy and several colleagues say they can fix this. For several hundred million dollars it would be possible to build a space-based telescope that, using something called a "coronagraph," would extract the light from a star and leave only the surrounding light sources, such as dust and planets. This technique JOEL ACHENBACH has already been used to detect a vast dust cloud, the type of thing that spawns planets, around the star Beta Pictoris.
"We believe it will be possible to observe planets around other stars," Levy says. "The discovery of planetary systems will be an historic occasion."
Yeah, and better yet: You'd never have to write a grant proposal again.
Q: Why don't you ever get carsick when you drive?
A: Most of our research about carsickness had been conducted in the bent position until just the other day, when we got hold of "What is Motion Sickness?" a report in the Annals of the New York Academy of Sciences that said, rather shockingly:
"The symptoms of motion sickness have been experienced at least since the invention of ocean-going vessels. It seems extraordinary that several millennia later, the fundamental nature of the disorder is still not understood. In particular, it is not clear why it exists at all."
Not clear why?!! Stand back - this is a job for the Why column.
First, some obvious points. When you drive a car, you're in control, you know when it will stop and swerve and turn, and so you can anticipate these movements.
But there's more to it than that. If you really want to find someone who has the time and the money to study puking-related phenomena in depth, you have to go to the federal government. At NASA's Ames Research Center, in Moffett Field, Calif., there's something called the Vestibular Research Facility. It's there to figure out why astronauts get sick in space.
The science director, David Tomko, told us that the key factor in motion sickness is where you're looking. You get sick because your eyes aren't stable. Normally your eyes can stand a certain amount of jostling - you could run through the veldt with a spear, chasing antelope, and your vestibular system will keep your eyes focused on the animal. You don't get motion sickness from hunting, jogging, playing basketball.
So, too, is it safe to sit in the driver's seat and look straight ahead; you are jostled but your eyes can adjust. But if you look out the side window at things whirling by, or try to read a book that's vibrating in your hand, your eyes can't adjust fast enough, and there's "slippage" in your vision.
But now comes the hard part: When the vestibular system gets overstimulated, why does that make you want to talk to Ralph on the big white phone?
No one knows. But a theory we really love - because it reinforces our longstanding belief that evolution is sloppy - is that you get sick because your brain thinks you've been poisoned. You experience symptoms - blurry vision, loss of balance - that are similar to those of poisoning. So the brain sends out the signal that you should purge the contents of your stomach.
But perhaps for now the best theory is simply that our vestibular system is designed to keep us upright, focused and balanced. Excessive rocking and rolling and bobbing and weaving is reckless and dangerous, and our vestibular system makes sure we stop by creating motion sickness. Certainly we were never designed to do anything so dangerous as drive at 65 miles an hour down a road.
"We did not evolve riding in cars and planes," says Tomko. "Evolution has not conditioned us for funny combinations of angular and linear acceleration that are passively applied to you."
If man were meant to drive, he'd have wheels. Something like that. Washington Post Writers Group
by CNB