From: Walter Watts (wlwatts@cox.net)
Date: Thu Aug 14 2003 - 16:52:02 MDT
Thought some of you astronomy buffs might enjoy this recap of astronomy
"legends".
Excerpted from Astronomy, October, 2000: "Strange Universe" column by:
Bob Berman
It took nearly a century for the public to realize that Mars doesn’t
have canals, and some still think that the moon doesn’t spin or that
Mercury has a frozen rotation. But the major persistent myths, the ones
that make backyard astronomers slap their heads and groan, probably
number just one or two dozen. We should make a list and send it to our
colleagues in the media. They can post it on some office wall with a
request: STOP SAYING THESE THINGS!
Water does not spiral down drains in different directions in different
hemispheres. It goes down randomly. Little imbalances in a sink or
toilet’s levelness or the direction of incoming water totally overpowers
the Coriolis effect caused by Earth’s rotation. Leap seconds are not
needed because Earth’s rotation slows down by a second every year or
two. If Earth’s spin decreased that quickly, we would have ground to a
halt eons ago. Leap seconds are mainly required because of the dispar-
ity between different time-monitoring systems. A day actually gets just
1/500 of a second longer after a century. A telescope does not “have” a
particular “power.” Comets do not visibly appear to move. Space shuttle
astronauts do not float around because they have escaped Earth’s
gravity. Even many teachers get this wrong. Nearly as much gravity
exists 250 miles high as it does on the surface. Astronauts feel
weightless for the same reason that skydivers do — because they are
falling freely. The moon does not pull on water or the oceans any more
than it pulls on your pet hamster. But because water can flow, it can be
easily displaced, which gives rise to the tides. There is no increase in
births at the time of full moon. The moon does not have a permanent
“dark side” any more than Earth does. Sci-fi books and movies and Pink
Floyd fans often allude to the “dark side” of the moon when they really
mean the “far side.” Jupiter was not “almost a star.” Even if it had 70
times more mass than it does, it could not sustain the nuclear fusion in
its core that would cause it to shine like a star. Meteorites are not
hot when they land. In 1991, one smashed into a lawn next to two boys in
Noblesville, Indiana, who immediately picked it up. They described it as
slightly warm to the touch. A meteor’s surface gets plenty hot when
incandescing 40 miles up, but the lower atmosphere’s sub- zero
temperatures cool it before it lands. From Pluto, the sun is not “just a
bright star.” The sun would be a point of light about 300 times brighter
than the full moon — too dangerous to look at. The analogy of planets
orbiting the sun and electrons orbiting an atomic nucleus is poor. Among
other things, atoms are a thousand times emptier than solar systems
relative to their components. Black holes do not go around sucking up
stars or planets; their diet consists almost entirely of nearby
subatomic parti- cles. If our own sun collapsed into a black hole (which
is not possible), Earth would continue to orbit it just as before. We
would not be pulled in. In fact, we wouldn’t experience the slightest
increase in the sun’s "pull", because its mass would remain unchanged.
But of course we would freeze to death. The northern lights are not
particularly colorful. Spooky, animated, incredible — yes. But many say
they see no color at all, while most perceive a pale green. Subtle pink
fringes are sometimes detected, but a deep red aurora is extremely rare.
This myth is probably created by color photography, which brings out
faint tints. Radio telescopes do not detect sound waves. Nonetheless,
people using them are almost always shown wearing headphones as if
they’re listening to something (as in the movie Contact). Those are some
of the most common errors perpetuated by the media. Lay people repeat
many more. For example, most folks are amazed to learn that only about
3,000 naked-eye stars can be seen at any given time from a dark
location. A rural sky seems crowded with “millions” of stars. Despite
how it’s depicted in movies, the asteroid belt is so empty of asteroids
that NASA could send a thousand spacecraft blindly through the belt
without much chance that one would hit anything. In fact, NASA directed
Galileo so it would encounter asteroids Gaspra and Ida. Galaxies are
mostly empty space. Stars are separated by such large dis- tances that
even when galaxies collide, their individual stars almost never do.
Contrary to popular perception, the universe has no center, just as the
surface of a balloon has no center. Because the Big Bang created both
space and time, it makes about as much sense to ask what happened before
the Big Bang as it does to ask what is north of the North Pole. The
public also imagines that professional astronomers look through
telescopes. The media perpetuate this myth by commonly having astron-
omers pose at the eyepiece. The moon’s size is another tradi- tional
source of error. Cartoonists make it enormous as it floats above lovers
in parked cars. Ask a friend how many moons must be piled on top of one
another to stretch from horizon to zenith and the usual answer is
between
15 and 50. The reality: 180. The moon is far smaller than people imagine
or remember it to be.
-- Walter Watts Tulsa Network Solutions, Inc. "No one gets to see the Wizard! Not nobody! Not no how!" --- To unsubscribe from the Virus list go to <http://www.lucifer.com/cgi-bin/virus-l>
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