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Re: (meteorobs) Clustering (a new approach?)...
> We could analize the minute by minute meteor data collected by some
> observers in different earth longitudes in search of "micro-streams"
> beeing crossed by the earth in its orbit. They would appear sequencially
> at every longitude from east to west with a determined velocity. Chris
> may help us here.
>
> But I too think minute by minute isn't a good resolution, as Chris
> pointed. Maybe we should collect data in tenths of a minute during major
> meteor shower.
That is precisely what I have been attempting to do with the Leonid data.
I've been getting the data whipped into shape, looking at it from a number
of different angles. The bad news is, it suggested some simple calculations
that yield disappointing results. Let's assume that we have a big Leonid
meteroid in orbit around the sun. It breaks in two with a relative velocity
of V; T seconds pass and the pair of Leonids hit the earth. What will be the
spatial and temporal separation?
Now, there's no simple answer to this question, because it depends on a
great many factors, most importantly the direction of the relative velocity.
However, it is possible to do a rough statistical calculation. It turns out
that there is a relationship between the temporal separation and the spatial
separation. If the two Leonids are observed just ten seconds apart, then
they will fall, on average, about 1,000 km apart. A one-second separation
implies a 100-km separation.
Now, this is a statistical relationship, so it is possible to get two
meteors separated by 10 seconds appearing close together in the sky -- but
such an event is rare. In general, if meteors are historically related, then
they will not be observable in proximity unless they have very short
temporal separations.
This is distinct from the previous calculations I had made regarding the
motion of the streamer path across the earth's surface.
Thus, it appears that data taken in one-minute bins is useless for the
purpose of determining whether there are any local spatial associations of
shower meteors. The only way to detect it is to have timings accurate to one
second in time and 30 degrees in angular position. This is precisely the
kind of data that my failed experiment was meant to obtain. Therefore, it
appears that our best hope likes in all-sky video recording of shower
meteors and a search for small-separation pairs.
Chris
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