[meteorite-list] Leonid Meteor Spectacle Coming Back Soon

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 10:06:14 2004
Message-ID: <200211061647.IAA24812_at_zagami.jpl.nasa.gov>

Sky & Telescope
Cambridge, Massachusetts

Contact:
Alan MacRobert, Senior Editor
617-864-7360 x151, macrobert_at_SkyandTelescope.com

November 1, 2002

Leonid Meteor Spectacle Coming Back Soon

After putting on spectacular performances for the last four
years running, the Leonid meteor shower will once again
sweep over Earth during the early-morning hours of Tuesday,
November 19th, Sky & Telescope magazine reports. If the
weather is clear, we could be in for a grand celestial show.

Every year since 1998 the world has witnessed an impressive
meteor shower around this date, when Earth passes through a
narrow stream of rubble in space left by Comet Tempel-Tuttle.
Meteor showers have long been hard to predict accurately,
but astronomers' experience with the Leonids in the last
several years has finally given them a good handle on the
subject. In 2001 meteor astronomers got it just right.
Countless thousands of skywatchers alerted by Sky &
Telescope and other news media went out before dawn at the
predicted date and time and witnessed the richest meteor
display over North America in 35 years.

This year meteor forecasters predict that we will again get
a strong shower -- and maybe even a "meteor storm" -- at
certain times on the morning of November 19th. They also
say this will probably be the last strong Leonid shower
that Earth will encounter for a century.

Unfortunately, bright moonlight this year will fill the
sky and compromise the view. Faint meteors will be mostly
hidden in the moonlight, though bright ones should show
through just fine.

According to the November 2002 issue of Sky & Telescope,
this year's shower is likely to come in two waves, each
lasting a couple of hours, that will peak around 4:00 and
10:40 Universal Time (UT, also called Greenwich mean time,
GMT) on the 19th. What that means to you depends on where
on the globe you are located.

The first peak is well timed for skywatchers in Europe,
North and West Africa, and northeasternmost North
America. The second peak favors all of North America, but
especially the central and western parts of the continent.

When is the best time to watch? That depends on your time
zone. Here's a rundown:

Eastern time zone

If you're in the U.S. Northeast or the Canadian Maritimes,
you can start watching the sky as early as 11:30 p.m. EST
on Monday night the 18th. The first peak will already be
passing, but not until about this time will the shower's
apparent point of origin (its "radiant" in the
constellation Leo) rise above your horizon, allowing any
meteors at all to reach your part of the world. Watch
for a few very long, spectacular streamers passing
overhead -- meteors skimming the top of the atmosphere
above you almost horizontally. They'll be flying roughly
east to west. Keep watching until at least 1 a.m.

The second peak should pick up steam before and during
dawn Tuesday morning. These meteors will be shorter and
perhaps more numerous. Start looking two hours or more
before sunrise (in other words, approximately 4:30 a.m.
EST; look up your local sunrise time in the newspaper or
use the almanac on Sky & Telescope's Web site and work
backward from there). The nominal peak should come around
5:40 a.m. EST. Depending on where you live, the meteors
may keep increasing in numbers right up until they fade
from sight in the growing light of day.

Central time zone

On Tuesday morning, watch from about 3:30 a.m. CST onward.
The shower is predicted to peak around 4:40 a.m. and will
probably be tapering off by the beginning of dawn. (The
first peak, described for the eastern time zone, is out
of sight from here and points west.)

Mountain time zone

On Tuesday morning, watch from about 2:30 a.m. onward. The
meteor shower is likely to peak around 3:40 a.m. MST.

Pacific time zone

On Tuesday morning, watch from about 1:30 a.m. onward. The
shower is likely to peak around 2:40 a.m. PST.

What direction should you look? "Up!" says Sky & Telescope
senior editor Alan MacRobert. "The meteors will appear all
over the sky, so just watch whatever part of your sky is
darkest. Keep the Moon out of your view so it doesn't
dazzle your eyes."

Here are some other meteor-watching tips. Dress very warmly,
because it will be colder than you think (due to radiational
cooling under a clear sky). Find a spot with a good sky view
and no bright lights nearby. Lie on the ground or in a
reclining lawn chair, preferably in a warm sleeping bag, so
you can keep a comfortable watch on the stars for a long
time without getting a crick in your neck. Just relax and
gaze into the stars.

You may notice that all of the Leonids have something in
common. Their paths, if traced backward far enough across
the sky, would appear to diverge from the same spot in the
eastern sky, in the Sickle pattern of the constellation
Leo, the Lion.

What is a meteor? What you're seeing is a white-hot streak
of superheated air caused by a sand- or pebble-size grain
plunging into the Earth's upper atmosphere at high speed.
The Leonids arrive at a blistering 44 miles per second
(71 kilometers per second).

Last year Leonids peppered the skies over North America at
rates of up to 1,000 per hour visible by any given observer.
Three years ago skywatchers in Europe and the Middle East
saw 3,000 per hour, nearly one every second. In 1966 lucky
observers in the southwestern United States gaped in awe
for 20 minutes as Leonids fell at the rate of 40 per
second! This year the visible rates may range from one
every few seconds to a couple of meteors a minute.

All this comes with a caveat. Meteor predicting is still
an inexact science. The only way to know for sure what
will happen on the morning of November 19th is to go out
and watch.

More about the Leonid shower appears in the November 2002
issue of Sky & Telescope, the world's leading astronomy
magazine, and on its Web site at
   http://SkyandTelescope.com/observing/objects/meteors/article_719_1.asp

Note to Editors/Producers: This release is accompanied by
publication- and broadcast-quality graphics and animations;
see details below.

Sky & Telescope is pleased to make the following images and
animations available to the news media
[http://SkyandTelescope.com/aboutsky/pressreleases/article_773_2.asp].
Permission is granted for one-time, nonexclusive use in
print and broadcast media, as long as appropriate credit
(as noted in each caption) is included. Web publication
must include a link to
   http://SkyandTelescope.com/
Received on Wed 06 Nov 2002 11:47:45 AM PST