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Re: (meteorobs) Angular velocities

Pierre Martin wrote:

> I would seem to agree with George's comments here. Recording data on 
> the field should be kept as simple or easy as possible to ensure 
> accurate data, even among more experienced observers. 

Are there any dissenters to that view?  The question at issue is
whether the different methods impose extra demands on the observer
during the watch.

> It would seem 
> to me that angular velocities or the 1-5 scale are about equally 
> accurate, since a small level of human error is possible (even 
> likely) when calculating angulars.

I'll look up the original WGN article so we have some numbers for
a comparison.

> Idealy, enough data and plots sent to IMO from many observers would 
> minimise the plotting uncertainty from a possible new shower? On some 
> nights, there may be too few observers watching, but over the years 
> data accumulates. With time, enough plots and velocity estimates 
> (regardless of the method used) from many observers would find the 
> radiant area, and basically narrow it down.

That's true for regular showers.  There's still a broadening of the
radiant, so while the reality of the radiant becomes more likely, or
the case of an established shower, the mean position of the radiant
becomes more accurate, judging how many meteors originate from the
radiant is still uncertain.  The radiant is more fuzzy.

> Once a target radiant area has been found by visual naked eye 
> observers, more precise methods like photography can carry on to 
> shrink the radiant area into a tiny point. A camera/shutter blade is 
> always extremely accurate (as long as it's properly set up), and only 
> a small number of meteors caught on film are needed to locate the 
> precise radiant. Does this make sense at all?

Problem here is that the rates are very low.  Some of these showers
have high population indices, so comparatively few bright meteors.
Video is more suitable.

Malcolm


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