Friends,
Perhaps due to confusion on my part or whatever, this response to
VK3QI's posting to me and copied to the Reflector has been gobbled up in
the bit bucket. Be that as it may, I put it here before you. Tomorrow, I
expect to have a response with regard to the satellite observations
mentioned in the text. But I am getting ahead of myself; read on:
To: <topband@contesting.com>
Date: Mon, 23 Mar 1998 07:46:48 -0800 (PST)
From: Robert Brown <bobnm7m@baker>
To: Peter Forbes <prforbes@tbsa.com.au>
Cc: topband@contesting.com
Subject: Re: TopBand: Further information on K1ZM's Echoes
Peter,
Thanks for the input on the matter at hand. Now a few words.
First, as I mentioned to you earlier, I monitor 55 kHz VLF signals and
got a dandy SID signature on the flare you mentioned. But the time
between that and the echoes troubles me.
First, the magnetic effects that Cary Oler mentioned were not very big.
I think he said something like the disturbance hardly affected the
K-indices. That is not what I'd expect from such a fast travel time; it
should have been a real "bell ringer".
Second, in my ignorance, I cannot put my finger on the proton energies
observed at the SOHO satellite. But there was not a PCA to the best of
my knowledge so we're talking about low energies. I would think those
particles, if they did get here, would have had limited access to the
ionosphere, probably the high polar cap.
But you're talking about ionization at lower latitudes. In that regard,
it is quite possible to have effects in both hemispheres at auroral
latitudes. I know that from experience, having observed auroral Xrays
over Macquarie Island and Alaska simultaneously back in March '62. But
that is still pretty high latitude, not the "banana belt" that seems
required here.
Sporadic E is an interesting idea and we can wait to see what the VHFers
say on that one in a future issue of QST. But in the chance that there
was some other effect that put ionization at lower latitudes, I have made
an inquiry with my friend in NASA who has the electron detectors on the
NOAA/TIROS satellites. They record continuously so now the question is
whether there was any ionization off the beaten (auroral) track.
Right now all bets are still up for grabs. The original matter about
long-path across a sunlit ionosphere is off the table. My suggestion of
echoes from ducting is just another variation on Cary Oler's remark about
multipathing. Maybe it was multiple F-hops but dipping down for ground
reflections is a costly affair when it comes to signal strength. The
real question is one of direction. So we'll keep working on that til
there is something new to throw into the pot.
I really have my reservations about a large blob of low-latitude
ionization but that's not a new position for me. Let's see that the
satellite tells us.
Cheers, Peter; hope your golf game went well.
73,
Bob, NM7M
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