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Re: (meteorobs) Re: Angular velocities
In a message dated 99-07-30 05:43:55 EDT, you write:
rob<<
One final point. Do observers compensate for zenithal attraction in the
radiant in assigning a meteor to a radiant?
>>
For most showers, zenithal attractions are relatively small with a few
exceptions....particularly if the radiant is relatively high up in the sky. I
don't consciously say to myself that "due to zenithal attraction, the meteor
missed the center of the radiant by so far etc." what I generally do is
provide enough of an area surrounding the center of a radiant to compensate
for the general misalignments that is part of being a human observer. The
artificially ballooned radiant diameter varies with the distance the meteor
occurs from the radiant. Up close, a radiant is roughly assumed to be several
degrees in diameter, while very far it could be recognized as 20 degrees.
These assigned large radiant diameters would generally also cover any
apparent spread of a radiant due to zenithal attraction as well.
GeoZay
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