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Re: (meteorobs) Possible radio outburst 1400-1500UT
Please note: The term "sporadic-E" pops up in radio meteor observations
quite often. Sporadic-E doesn't mean sporadic as in sporadic meteors in
this case but rather means "happening in scattered intervals of time". E
refers to the E-layer of the ionosphere. Sporadic-E or Es is a not
completely explained radio phenomenon in which a temporary conductive cloud
forms in the upper atmosphere which causes extraordinary long distance
radio receptions at certain frequencies. These frequencies coincide with
radio meteor monitoring fequencies and hence can act like interference for
the radio meteor observer.
Jim Richardson wrote:
>>>...I did not read your report until the afternoon, and at that time, my
system showed only light Sporadic E with a normal meteor background.<<<
Wednesday July 24, 1996
Jim and everyone,
Thanks for the thoughts.
I will pursue analysis of the possible outburst today. Stressing to all
this list the word.."possible." That's a most important word in these
cases.
I have studied all the sporadic-E episodes this year that have effected my
observatory that have made it up to 90 MHz and have noted its qualities.
I've listened to hours of Es under headphones and have attempted to track
its movements. I have gotten Es literally from Washington State to Quebec
to Central Mexico to Georgia. It's quite dynamic but generally hasn't
displayed multiple sudden onsets like individual meteors make. Yet I have
had some double hop skip that sort of "bounced" dynamically into the whole
weird mix of the sporadic-E episodes. I need to look into this more in this
possible July 23 outburst case. If this was some sort of sporadic-E then
hopefully it can be correlated somewhere in the sporadic-E community.
Garth Klatt, a fellow radio meteor observer in Calgary Canada was observing
yesterday and he reports no special activity. But he is 1000 miles or more
to my north and has a different sky, yet we have correlated on other
showers when a shower radiant is in mutual sight.
Fellow western US observer Jim Riggs reports enhanced activity but it was
on a new chart recorder so the recorder's stability must be scrutinized in
this one day's case. I will dialogue with Jim more on this.
But Jim's record is intriguing. With his permission I post his report and
numbers:
>>>Tom 23:50 UT 23 July 1996
I found your report of a possible meteor burst. I started recording data
at
18:30 on 22 July 1996, I am recording on the chart recorder at 1mm/minute.
Anyway it was my first serious run and I was anxious to see if I got any
indication of an increase in activity on 23 July 1996 during 1400-1500-1600
and continuing. Sure enough at 13:59 UT(6:59 am PDT) I got a strong
signal
that appeared to have fireballs until 40 minutes later the pen was hitting
the
top and at that time I changed the recorder level so I am not sure what has
gone on since then. But if I had to give an opinion I would say it went on
much beyond 1600.
I have another system which collects data for Peter Jenneskins. I checked
the
computer hourly counts and got the following: 02 to 09 UT--<7 counts;
10UT--13; 11UT--29; 12UT--33; 13UT--87; 14UT--513; 15UT--27; 16UT--23;
17UT--24; 18UT--214. At this point in time I took the data. I have not
looked at the computer since then.
What do you think, am I getting viable data? I just started collecting and
don't have a backlog of experence that you have..
Jim
P.S. The high activity lasted so long maybe it is sporadic E?<<<<
That is Jim's initial report. (Unofficial)
So this is encouraging at least of possible meteor activity. Now the task
will be to see if any meteor mocking sporadic-E was observed anywhere.
This is an interesting exercise by the way. I have been monitoring non-stop
for the past year. Prior to this year I monitored known showers. Over the
course of the year I think I have noted a few episodes of "more enhanced"
activity but never enough to put out an alert. Sometimes I have noted
passage through non-shower "clusters" but these haven't lasted more than
minutes. I have passed through many days of sporadic-E as well without
getting too excited.
Yesterday was unique in my radio experience up to this point. A typical
non-shower day consists of the base meteor background, the dawn sweep,
maybe some Es for spice, and some random fireballs.
Someday it would be interesting to observe a verifiable outburst on a
forward scatter array and then alert a radar array to scan for its radiant.
Maybe in the future there will be a co-operative network like this.
More later,
Tom Ashcraft