Satgen 602  Leonid MS 17/18 Nov  by GM4IHJ   (BID SGEN602) 2000-10-07

It is getting near that time of year , when the great guessing game
we call the Leonids Meteor shower , comes around again. This shower
occurs every year as the earth passes through the dust stream left in
the wake of Comet Tempel-Tuttle. Dust trails which are reckoned to be
at their densest in years just after Tempel-Tuttle has made its
perihelion closest approach to the Sun, on its 33year passage around
its orbit. A perihelion which last took place in 1998.

So 1999 was expected to be a good year. It did not rival some of the
great Leonid showers of history , but it was a superb event, if you
got your timing right. Unfortunately not everyone did. Radio
astronomers able to observe both in daylight and in darkness,
appreciated on the afternoon of the 17th that a good shower was in
progress, and were able to follow it through the night . Observing
the best peak for about 40 minutes either side of 0200z on the 18th.
Followed 14 hours later by a secondary lesser peak at about 1600z on
18th. While observers who thought the peak would come later still on
the evening of the 18th, were poorly rewarded .

Which makes predicting this year 2000 peak a little difficult. With
experts disagreeing, the best bet seems to be keep your radio on all
the time and use it to alert you , to when, if the night sky is clear
you may see something exciting.

Predictions of Leonids 2000 peaks, available to date, are shown below
:-

McNaught     0344z and 0751z on the 18th

Ferrin       0924z on the 17th

While straight forward old fashioned extrapolation from the times of
the 1999 peaks at 0200 and 1600z on 18th . Suggest plus 6 hours later
for sidereal time correction, and minus 24 hours because we had a
leap year day on Feb 29 2000. Which works out as a shift back from
the 1999 figures of 18 hours , producing a crude prediction of :-

Old Fashioned Extrapolation   0800z and 2200z on 17th Nov

ie nowhere near McNaught but close to Ferrin

At IHJ the 6m receiver and antenna will be set to monitor a Norwegian
TV station carrier at 48.2533 MHz tuning point, for a very clear 700
Hz note when set to receive CW. Audio will be on loud speaker and
will be fed to the FFTDSP DSP program ( by AF9Y) for computer
spectrum analysis. Please note that most of the TV carriers are off
from their local midnight to their local 0600 . So at IHJ that period
is covered by monitoring the GB3RMK beacon on 50.061 MHz CW.
Listeners in other areas should use VHF TV stations between 500 and
1000 kms from them or suitable 6m beacons. If you have no VHF TV try
Band 2 FM stations around 72 MHz in Easter Europe, or 88 MHz upwards
in other areas.