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Re: (meteorobs) Sporadics and wavelets



Lew Gramer wrote:
 
> But I'm not sure that even meteor science
> would incite me to ever program in QuickBasic again... 

Its better than Fortran77 :-)


> 
> I guess a day would be sufficient granularity, so long as you were dealing
> with data that was appropriately corrected for diurnal variation and
> radiant height. But doesn't this bring up another problem? - I wonder how
> you can do radiant height correction for "radiantless" meteors, not to
> mention meteors from unknown minor radiants? And without that correction,
> isn't it too easy to bias analysis with geographic- and time-local data?

A real good question to ask the radio meteor guys.  Don't get me wrong
here.  I'm interested in meteor photography.  But even with high
resolution film photography, you need data from two sites, each with
dual cameras (one siderial tracker, one fixed) to really be sure of the
radiant.  Furthermore, I think you are looking at automated sites to get
the quantity of data you would need, watch out for the cost of reducing
and archiving data, etc to get a credible annual database, which
reflects only the extreme dark sky time of day.

I am not saying that this is undoable, just that to produce useful data
we have to watchout for the some potential pitfalls.

> 
> So it seems like you actually have to do analysis with hour- or even
> minute-granularity, and decompose these cycles out, no? As I understood it
> from Dr. Meisel, he was interested not only in spotting short-term "pulses"
> (i.e., individual minor showers), but also longer-lasting signals (e.g.,
> seasonal and subseasonal variations - effects which presumably might relate
> to solar system motion, orbital resonances, etc!) Hm... :)

I was trying to get at what you have just expressed more clearly.  If we
are trying to spot seasonal trends in terms of a resolution measured in
days, then the visual/photographic approaches are much more likely to
produce useful data.  I mean photographic to include video cameras as
well!  Video camera may have the potential to better spot minor showers,
but trying to process the wealth of data provided by such cameras could
be a challenge.  The plus side of video cameras is that you don't need
siderial tracking.  A negative consideration is the cost.

It would be a neat experiment to record data from two video cameras
about 30 km (20 mi) apart, pointed to cover a common volume of the
extreme upper atmoshere.  Next see if we can analyze it and ball park
the computing horsepower.

FWIW, I have experience in installing video cameras which must operate
under environmental extremes.  As amateurs, we can make suitable
environmental enclosures without breaking the bank, and things like pan
and tilt adjustments as well.  Not having to operate in daytime is a big
advantage.  Reliable cooling is more expensive than heating. :-)

Regards,
John
--
John Ohrt,  Regina, SK, Canada
johrt@ibmdot net



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