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(meteorobs) Re: Last Minute Leonid Info and Tips



admin fwd from: B Yen <byen00@earthlinkdot net>

Is there any reason to go out Nov 16-17 or Nov 18-19?  The below implies
the Nov 17-18, to coincide with predictions.  I remember in '98 (fireball
show), that the night before the "peak" showed increased activity.  (I even
heard from someone, it was even *better* than the peak period).


B Yen

Robert Lunsford wrote:

> The Leonid meteor shower occurs every year between November 14 and the
> 21st as the earth encounters particles left behind from comet
> Temple-Tuttle. This comet orbits the sun every 33.25 years and leaves
> debris in a slightly different path with every return. The debris the
> earth encounters is normally sparse creating no more than 10-15 meteors
> per hour at best.
>
> What makes this year exceptional is that the debris fields or paths
> orbiting near the comet, which last passed the sun in 1998, has a much
> higher concentration of material than in normal years when the comet is
> far from the inner solar system. In 2001 the earth will pass close to
> three separate paths of the comet. These paths were created by the comet
> in 1699, 1767 and 1866. When the earth passes close to each one of these
> paths there is the chance of increased meteor activity.
>
> The first encounter will occur when the earth will pass close to the
> path created in 1767 near 10:00 Universal Time on November 18. Observers
> in extreme northwestern South America, Central America and North America
> can see this possible outburst. This time corresponds to 2:00 AM Pacific
> Standard Time and 5:00 AM Eastern Standard Time. Rates as high as 30 per
> minute have been predicted at this time.
>
> The second possible outburst will occur some seven hours later near
> 17:30 Universal Time. This outburst will be caused by the path created
> in 1699 and is best seen by observers in eastern Australia and all of
> the western Pacific region including Japan, Korea, and eastern China.
> This time corresponds to 1:30 AM in Korea and 4:30 AM in eastern
> Australia on the morning of the 19th. Rates as high as 30 per minute
> have also been predicted at this time. By this time the Americas' will
> have moved into daylight, with the sun obscuring that region from seeing
> further activity.
>
> The last possible outburst may be the best as the earth passes very
> close to the path created by the comet in 1866. Closest approach occurs
> near 18:15 Universal Time which is only 45 minutes after the 1699
> encounter. This time favors the same regions mentioned above for the
> 17:30 outburst. Rates as high as 100 per minute have been predicted at
> this time. Another reason the predicted rate is so high is that there is
> the possibility that the material from the 1699 path will still be
> active thus we have activity from both sources occurring
> simultaneously.
>
> Please note that these times and rates are only estimates. We cannot
> predict with 100 percent certainty the exact time and activity since we
> do not know the exact location and intensity of each path. The actual
> times and strengths may differ considerably. The key is to be out at
> least an hour BEFORE these times just in case the outbursts occur early.
>
> Leonid meteors cannot be seen during the early evening hours. These
> meteors can begin to appear as soon as the radiant (the area of the sky
> the meteors seem to originate) rises in the east. This occurs during the
> mid evening hours for high northern latitudes, late evening hours for
> mid northern latitudes, and after midnight for those located in
> equatorial regions and the Southern Hemisphere.
>
> When the radiant lies near the horizon the Leonid meteors cannot
> penetrate far into the earth's atmosphere. At this time they are only
> able to skim the upper atmosphere. Meteors seen at this time are called
> "earthgrazers" and can be quite spectacular. They often last several
> seconds and can span a great distance of the sky.
>
> As the earth rotates and we move into the morning hours the Leonid
> radiant will rise higher into the sky and the meteors will strike the
> atmosphere at a more direct angle creating shorter paths. These meteors
> may be less striking than the earthgrazers but they will certainly be
> much more numerous as less of them will be obscured by the horizon.
>
> Tips for watching the shower:
>
> 1. Watch near the times indicated above on the morning of the 18th for
> those in the western hemisphere and on the morning of the 19th (local
> time) for those watching from eastern Asia and the western Pacific
> region.
>
> 2. Watch from rural areas free from light pollution. While a few meteors
> may be bright enough to be seen from cities, most of them will be
> fainter and will be obscured by bright city lights.
>
> 3. Be comfortable! Don't stand and watch. Use a lounge chair and
> blankets to make yourself comfortable.
>
> 4. Don't watch for 5 minutes and give up if you don't see much. Meteors
> often appear to arrive in bursts. A few minutes may go by with little
> activity and then you may see a sudden burst of activity the next
> minute.
>
> 5. Leonid meteors can be seen in any portion of the sky. It is probably
> best if you face the darkest direction available at your location. The
> typical Leonid meteor last much less than one second and often leaves
> behind a persistent train. Leonid meteors seen close to the radiant and
> close to the horizon (in any direction) will appear shorter and slower
> than those seen high in the sky far from the radiant. Just be sure to
> look up at least halfway into the sky so that none of your field of view
> is wasted on the ground.
>
> 6. Make this a family event! Since this is a Sunday morning in the
> Americas', get the entire family involved. Next year's shower is
> hampered by a full moon and after that it will not be until 2099 that we
> see Leonid activity this strong again.
>
> Wishing you all clear and meteor-streaked skies!
>
> Robert Lunsford
> AMS Visual Meteor Program Coordinator
> The archive and Web site for our list is at http://www.meteorobs.org
> If you are interested in complete links on the upcoming LEONIDS, see:
> http://www.meteorobs.org/storms.html
> To stop getting email from the 'meteorobs' list, use the Web form at:
> http://www.meteorobs.org/subscribe.html

The archive and Web site for our list is at http://www.meteorobs.org
If you are interested in complete links on the upcoming LEONIDS, see:
http://www.meteorobs.org/storms.html
To stop getting email from the 'meteorobs' list, use the Web form at:
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