Leonids: initial meteor scatter results

[BiggarDigger]

My initial results from last night's shower show an interesting double peak, with an unusual dip between 3am and 6am, where I would have expected the peak to occur.  I also recorded some incredibly long duration events too.

This is my heat map recording all events in November up to this evening.  It is not filtered for duration, so there will be a little background noise, but should be pretty representative.  The gap on the morning of the 14th is a poorly implemented Windows update, where I had to go to work before it completed.

There's a peak in activity early in the month, which I'm uncertain of the source.  The Northern Taurids appear to be well defined on the early morning of the 12th and the Leonids appeared to be building nicely with a similar early morning peak.  Early this morning however appears to show a drop in the count and duration.  It wasn't particularly bad weather, in fact it was fairly clear I think, so we should have had no dampening effect due to tropospheric absorption/scattering.

Although there was a noticeable drop in meteor count, there was some extremely long bursts during, including during the quieter time.

Duration here is in seconds, and yes there was a couple of bursts approaching 2 minutes:

 

Given my range and northerly direction to the main beam from GRAVES these long duration events are unlikely to be related to tropospheric ducting or similar.

It will be interesting to see the results from the tonight and then look forward to the Geminids.

Richard

 

 

 

[BiggarDigger]

Sorry for replying to my own post, but it's worth an update after collecting further data from the 20th and most of the 21st now.

The morning of the 20th showed what appears to be a similar, if smaller double peak and this morning was pretty much back to a normal early morning single peak.

Here's my updated heatmap, again not filtered for duration:

 

The extremely long duration bursts continued well into the morning of the 20th.  I noticed earlier this month that I was recording some strikingly long duration bursts, which were wrapping the Spectrum Lab display, so I stretched the display out to two minutes on the morning of the 14th.

I'm glad I did, because here's a couple of charts of maximum and average duration from midnight on the 13th (each horizontal tick is an hour):

 

 

Based on the recorded events at my location the the peak was broadly spread across the 19th and 20th.  However, and this may be a big caveat, assuming the duration of the event is somewhat proportional to energy of the strike and therefore somewhat proportional to the mass of the meteor (assuming the velocity is roughly constant across the range of meteors), on the whole larger, more massive meteors were recorded on the morning of the 20th rather than the traditional peak of the 19th.

There's some pretty big assumptions in that statement, so I'm not making firm scientific claims based on the data, but it's interesting nonetheless.

I've not had time to convert the duration of events into seconds on those charts so they are recorded in cycles of the Spectrum Lab algorithm, where 1 second is roughly 10 cycles.

Another interesting item to pick up is the event that ended at 11:56 on the morning of the 17th.  This was recorded as being 1978 cycles long (roughly 200 seconds) before it stated to fade - but even then it had a further 20 or so seconds of weaker scattering fading in and out of the capture range of the system.  Further long duration events occurred through the peak across the 19th and 20th with many events over 100 seconds and a couple in excess of 150 seconds.  Most of these wrapped round the extended window I had set to record, e.g. that super long burst of 17th Nov between approximately 1153 to 11:56:

 

A pretty amazing shower: perhaps not the storm that some people expect from the Leonids, but wow, those long duration bursts!

Looking forward to some decent strikes from the Geminids now.

 

Richard

[Stub Mandrel]

Nice captures and data.

I will set up for the Geminids, I saw a couple of excellent meteors, one probably counted as a fireball, on my birthday (17th).