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Re: Velocity estimates
Lew Gramer asked:
>What's considered to be the maximal achievable accuracy of such amateur
estimates? How accurately do you try to report them, George? Mark?
>Norm? Do people only report speeds as km/s when plotting, or for major-shower
>counts too?
As a reminder, when observing major showers, especially at maximum, the
meteors appear at such at rate that plotting becomes impossible. There is no
way to keep up with the activity, thus the switch to counting methods.
Likewise, an observer might find it difficult to record all data concerning
a meteor such as shower, magnitude, time, any train, color, velocity, etc.
So a trade off is required...you may have to drop some of the data
collected. Personally, the first piece of data I forget about is color, for
the reasons previously discussed here. The IMO has dropped velocity
estimates from their visual counting forms, I assume, for the same reason.
Therefore, strictly speaking, I guess we could say velocity estimates are
done only during plotting, but in practice, I estimate velocity whenever I
am able. When counting, these estimates get reported to ALPO, but not IMO.
Velocity tables are set up in increments of 5 km/s, based on a meteor's
beginning point and distance between radiant and end point. Perhaps Rainer
could provide what the maximal achievable accuracy is since he has a larger
sample of observations than I do from NAMN/ALPO data. Has this been
determined yet Rainer?
mark