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Re: Lyrid Meteor Shower Reminder

Bernd schrieb:

>  There is no major meteor shower in June, whereas the Geminids (Dec.
>  13-14, ZHR = 90; 34 km/s) occur when there is a minimum of meteorite
>  falls.

GeoZay wrote:

> Just a note .... The ZHR for the Geminids has been adjusted upwards in
> recent
> years by the International Meteor Organization. It is now at 120.

Hello George, hello List,

Your email prompted me to browse some Sky & Telescope Calendar Notes. In
the Dec 1996, p. 79 issue, you find that, according to the IMO, the
maximum ZHR reached 140 in 1993, 'whereas in the late 1980s, 100 was
more common'.

Question 1: Has this specific ZHR caused the upward adjustment or has
there been observed a steady increase ever since 1993?

Question 2: What does this increase imply? - If a comet was responsible
for the debris, we might conclude that this comet is on its inbound leg
and approaching Earth but, as you say, it's asteroid 3200 Phaethon and
not a comet.

The same Sky & Telescope Calendar Notes continue with another
interesting note: 'Rates increase steadily for several days before
maximum, then drop off quickly. THE METEORS THAT DO APPEAR AFTER MAXIMUM
ARE OFTEN ESPECIALLY BRIGHT '.

Question 3: Does this mean that the particles the Earth encounters
during the Geminid maximum are smaller than the ones that enter Earth's
atmosphere after maximum? - If so:

Question 4: Does that mean that the Earth and the Geminid meteors meet
at exactly the same time each year in spite of possible perturbations by
other planetary bodies?

Best wishes, Bernd

P.S.: As we have the last day of the Easter Holidays here before school
begins again tomorrow and because it is a rainy Sunday afternoon, the
Internet access is so crowded here that I may not be able to answer any
emails. So don't think I am impolite if you do not receive any messages
from me. The email I posted at 17:15 had been written almost three hours
before but I just couldn't access the Net. Let's now see if I can send
this one directly.