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(meteorobs) Radio-monitoring of Leonids

Dear Colleagues,

I read in NASA press-release and in other Leonids -2000 news in internet
that NASA
supposes to set 1-2 VLF radio-receivers for detecting possible VLF emissions
from
Leonids. Here I would like to do a couple of remarks.
In my opinion, there can be 2 main sources of electromagnetic radiation
from Leonids:
1) Due to their high speed they intensively interact with ionospheric layer
E,
where various plasma waves can be excited. If Leonid's angle to geomagnetic
field, etc. are appropriate to their coupling with some modes of the plasma
waves in
the layer, they could transfer part of their kinetic energy to the waves.

2) In certain geophysical situations a meteoroid can be a trigger of
natural/geophysical plasma waves in the ionosphere, as producing parametric
instability in ionospheric waveguide, precipitation of charged particles
from radiation belts, etc.

There can be also some additional source of the VLF radiation inside a
meteoroid's wake itself, but I incline to think that it is less important.
Anyway,  the supposed VLF radiation associated with Leonids is to be rather
complex. Those who are interested to read more about the plasma
instabilities could read my AIAA Paper 2000 - 0589 (I posted it  at:
www.geocities.com/olkhov/meteors.htm ).
In 1940s there was a Russian report on detection by SW (short wave)
radio-set of meteors on high-latitude region. They were heard as noise.

That's why it would be very important to conduct detailed investigation,
including simultaneous monitoring particle precipitation, ionospheric
data/parameters, electromagnetic environment etc.
Anyway, it would be useful (while observing meteors) to have a radio-set
nearby, tuned to free (i.e. without radiostation's signal) frequency of its
band (to have several radio-sets tuned to several different bands would even
more useful, of course). Who knows, maybe some inportant data  will appear?

Sincerely,
Andrei Ol'khovatov,
Russia, Moscow
.









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