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Re: (meteorobs) Re: Swift sporadics
In a message dated 98-09-15 19:13:25 EDT, you write:
<<
This discussion is another reason why I favor the IMO's endorsement of
measuring meteor velocities in degrees per second and not the vague
numeric scale, at least for experienced observers.<<
Whether you use the numeric scale or in degrees per second it doesn't matter.
They are both "vague" in practice. Neither one is useful in accurately
measuring a meteor's velocity for any purpose other than shower association.
The purpose of either method is not to obtain a meteors velocity measurements,
but rather a means to reasonably determine whether or not a meteor is related
to a particular shower. I think determining degrees per second is a lot of
needless mental gymnastics. Simply noting the speed impression of a meteor and
being familiar with how a location of a meteor to it's radiant will effect
it's apparent speed is quite simple and just as efficient for the purpose that
speed measurements are used for. The numeric scheme works quite well for
this. If you desire to mentally count how many degrees a certain meteor has
traveled and then estimate the length of time that has passed when the meteor
was visible...have at it. But when you are plotting meteors, there is enough
to memorize or occupy one's mind already. Such as magnitude and trajectory so
that you can make that plot with a little more degree of accuracy. The numeric
method is a lot easier to use and learn how to use with no significant
disadvantage when interpreting the results for shower association. There are
less disrupting mental steps with the numeric method than the degree/sec
method during the actual observations. If I don't make a shower association
while observing (for plotting purposes), I can still easily do it the next day
from my plots during the "next day" report making very conveniently.
George Zay