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Re: (meteorobs) Re: Cepheus Meteor Activity Dec 5?
In a message dated 97-12-14 10:47:27 EST, you write:
<<
I found it useful to give an estimate of the upper velocity limit of a
potential meteor shower. I assumed a radiant position at alpha=335deg,
delta=+65deg, directly within the box of Cepheus. This position has a
distance of 108deg from the apex of the Earth's motion. The further the
radiant distance from the apex, the smaller the geocentric velocity. If I
assume 42km/s as the maximum heliocentric velocity of any solar-bound
particle, I get 21.5km/s geocentric velocity -- and 24km/s maximum entry
velocity into the Earth's atmosphere. Since the radiant was high in the
sky, the meteors should give about the same picture like the kappa-Cygnid
meteors. The radiant was roughly 60deg above the horizon, the fastest
meteors should then appear in Pegasus with about 10deg/s speed. So all
meteors should be a the low end of the velocity range. The velocity
impression of the guy cited is certainly not accurate; nevertheless, I wish
to show how such calculations may help judge whether or not a suspect
radiant is real.
Rainer Arlt
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Rainer, I kinda figured the velocity range the individual gave was too fast
also. But considering that the individual isn't an experienced meteor observer
and don't really know what their interpretation of Slow or Medium velocities
may appear to them, I was lenient with that part of the report. Probably
nothing in reality...but close enough to be suspicious.
George Zay