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(meteorobs) Possible radio outburst 1400-1500UT

Mark Davis wrote: >>>...Pardon the question from a non-radio observer, but
are you saying that currently it is not possible to tell all sporadic-E vs.
true detections? Or only just difficult to do? Also, is it known at what
height the conductivecloud forms?...<<<

Mark,  Good questions.

According to McKinley, the E region of the ionosphere is roughly 100 to 120
km high. But in perusing METEOR SCIENCE AND ENGINEERING I can't find a
specific height to sporadic-E clouds.   

Sporadic-E (or Es) causes interference to the radio meteor observer because
the conductive cloud can cause very strong, erratic episodes of reception
of far distant transmitters that would not occur under "normal" conditions.
Es swamps the radio.  

You can distinguish Es from meteors as Es generally fades in and out and
makes longer receptions than meteors. **Radio meteors appear suddenly.**
Though I have heard some erratic Es that had sharp onsets. 

But there are subtleties, too. There are certain meteor showers, most
notably the August Perseids, that can cause a more dynamic sort of
sustaining meteor reception. For example, if you are passing through a
denser Perseid ribbon or debris belt, you can get a cluster of meteors and
fireballs that will cause greater and longer lasting ionization which will
cause unbroken minutes of reception of a faroff transmitter.  The radio
Perseids can be a problem to count because at times you won't receive
individual meteors when the mass of meteor reflections are causing a
constant connection with the far off transmitter. Passages through debris
belts with sustained reception only happen during certain major showers.

Regarding the July 23 1400UT "possible outburst":  I am now wondering if
there was a coincidental higher number of fireballs (possibly unrelated to
one another?)  that may have caused a sustaining reception similar to what
the Perseids can make. 

Could this have been fireball induced Es?  (Just a question.)

Or could that 1400UT hour have been a combination of low level Es and
meteors reflecting through with a higher number of fireballs ( possible
early Perseids? ) that was out of the ordinary in terms of normal meteor
conditions but may not have been an actual shower "outburst" (like last
year's  alpha Monocerotid shower outburst for example).

Well, we may never know since it happened in the daytime. I don't think
there has been a sustained daytime radio meteor study that lasted over
decades. Some outbursts may only occur every decade or so or more and just
show a half an hour's sharp peak. I think the alpha Monocerotids only made
200 or so radio reflections in the course of one hour or so. (I could be
wrong on that figure.)

So there will surely be fresh discoveries made and new comet tails to cross
through.

Regards,
Tom Ashcraft