(meteorobs) Solar activity and meteors (reply)


Thank you for the note about the connection of meteor rates to solar
activity. I don't think I was telling there is no relation, I just noted
that the height of the ionosphere may not affect meteor rates, whereas the
air density does, and this is what you also indicated citing several
papers. I find "well established" a little exaggerated when talking about
observational evidence. We have to bear in mind that it is always only one
solar activity period which is covered by a single publication. Several of
them together indeed hint on a consistent picture. I tried to extract
sporadic rates from the VMDB 1984-1997, and I only used those obtained
between 2200 and 0200 hours local time and those noted in July, since this
a month covered by many observations and is not affected by a major shower.
I did not find any correlation. Here is the data:

Year  sporadic hourly rate
1984  14.8
1985  12.6
1986  15.6
1987  18.0
1988  12.8
1989  13.9
1990  14.7
1991  15.7
1992  18.0
1993  15.1
1994  14.8
1995  15.3
1996  17.6
1997  15.3

(By the way, I was satisfied by the overall constancy of the rates, which
does not support the suspicion about rates inflating during the last

Of course, this is just a quick look in the data, more can certainly be
done. Nevertheless, we don't have much more than one cycle either. When
looking at the graphs of PER and ORI in Peter Jenniskens' article, I would
like to know how other shower behaved. I guess enough data should also be
available for the Geminids, eta-Aquarids and Southern delta-Aquarids
according to Table 3a.

The analysis will be an interesting task using a long series of visual
observations (more than 2 solar cycles). I am keen on seeing more on this.

Best wishes, Rainer