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Re: Leonids

In a message dated 98-04-24 01:17:46 EDT, you write:

<< 
 What are the pronostics for the Leonids this year?
 
 Edgar Castro >>
----------------
Edgar, 
Here is my little ditty about the 1998 Leonids. 
George Zay

LEONIDS - The Leonids are a shower of short duration, lasting only
one week centered on November 16/17. The Leonids are particles 
from comet Temple-Tuttle, which will reach perihelion in 1998. A 
great concentration of particles exist near the parent comet. In 
years when the comet is far from the inner solar system, the acti-
vity remains below 10 meteors per hour. However, for approximately
10 years centered on the perihelion passage of Temple-tuttle, the
Leonids can produce high rates of activity. This is one of the
years everyone has been waiting for. The possibility of a storm
exists and should be anxiously awaited. 1997 activity dramatical-
ly increased with ZHR's well over 100 for the U.S. West coast. 
This year the peak is expected to occur over China near 18h30 UT.
If your Longitude is near China's you stand a good chance to see
a good show. A storm lasting about 1 hour is possible there. For the rest of
the world, ZHR's should be quite high, perhaps reaching 200 or
more? Begin observing around 23h00 hrs local. Activity will in-
crease as the night progresses. With periods of high activity,
the Leonids are easy to photograph. Many shower members are
bright and leave long lasting trains. The 1998 return will be
under ideal conditions with a New Moon on Nov 19. Photographers
should use a variety of camera's and lens at wide open settings.
I personally will be using a 28mm at f/2.8 and a 50mm lens set
at f/2.0. Use a black and white 400 ASA film such as HP-5 or
Tri-X and aim your camera towards the North East elevated at a
50 degree angle. Make exposures between 2 and 30 minutes. The
Leonid stream collides with the earth from a head on position
that produces the highest velocity of all major showers. For-
tunately the Leonid radiant is located close enough to the Cel-
estial Equator that these displays may be enjoyed by both hem-
ispheres. Max: Nov 16/17,1998 at 18hr UT; ZHR: 100+; Vel. 71
km/s(Very Fast); Duration: Nov 14-21; Population Index: 2.5;
Radiant Diameter: 5 degrees; Train Production: 58%; Radiant:
RA 10h12m, Dec +22; Three Letter Shower Code: LEO