The meteors or "falling
stars" that you commonly see in the sky are pea sized pieces of rock and
ice, solar system and comet debris, that happen to strike the earth's
atmosphere and "burn up" at altitudes of 70 miles or so. On any arbitrary
night of the year, there are a few "sporadic" meteors; perhaps 15 or so
per hour. Several times during the year there are "showers" of meteors,
when you may see 20 - 60 additional meteors per hour which, although they
appear in all parts of the sky, seem to be coming from a particular point
in the sky called the radiant. The shower is named after the radiant,
like the Orionids, which peak about October 12, and appear to radiate
from the constellation of Orion.
The best two regular showers of the year
are the Geminids about December 12 and the Perseids about August 12. During
these showers you may see 60 or more meteors per hour. To see meteors
well, you need to go out to a dark sky site. We always see more meteors
after midnight; then we are on the side of the earth facing forward along
its motion around the sun, so we run into more space debris. The best
way to watch for meteors is to dress warmly and lie back in a lawn chair
so you can see the whole sky. Have a blanket or sleeping bag handy for
additional warmth.
The Leonids are a regular small shower about Nov 17
each year. But the Leonids are known to peak every 33 years, sometimes
in a meteor storm with thousands of meteors per hour. In 1966 observers
in the SW US saw 150,000 meteors per hour! Watch for this "End of the
World" Leonid meteor storm in the early morning hours of Tuesday morning
Nov. 17 in 1999. Unfortunately, the expected peak in the meteor rate doesn't
occur until after dawn on the West Coast, so we have to hope to see a
build-up towards the maximum rate as dawn approaches. Observers in Asia
have a better chance to see the peak of the storm. Of course, there is
always a chance that the predictions a little off and the peak comes early
or late. NASA is taking this event seriously, and closing down the Hubble
pace Telescope and pointing it away from the storm radiant, and taking
what measures they can to protect the other satellites. For more information
about the Leonids, click here. |