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Hi All,
I had partially clear skies 16/17 and last night 17/18 was completely clear. Despite the very bright moon I captured a reasonable haul of Leonids plus others.
Got one really interesting spectrum at 20241118_013019UT. Unfortunately and extremely annoyingly I didn’t get the blue end. The UKMON reports site has it listed as a Leonid. This is the first Leonid spectrum I’ve captured with my latest HiReMS II cameras.
Yet to be fully analysed.Bill.
Hi,
Caught another Type C last night. This is a much more regular capture… a partial spectrum and in the first order only.
Doesn’t quite cover the same span as the super high resolution one, ~427nm to 592nm, but it’s interesting to see the how all the extra lines emerge between the usual “strong” lines.
Cheers,
Bill.Attachments:
Hi Jack,
Thanks, the software I use is IRIS for the geometetric corections and Visual Spec for the spectroscopy. Both free packages and I’ve been using them from nearly 20 years!
There are now probably more modern software options avaialable but as I do the “fitting” manually these work well for me.
Cheers,
Bill.Hi,
A re-work of the synthetic spectrum. From ~430nm to 591nm
Cheers,
Bill.Attachments:
Hi,
I also used to correspond with Ed, I don’t know if you’re aware but Ed died last year. I only found out myself earlier this year after emailing some other Canadian collegues. He was always very encouraging, he persuaded me to persevere after decades of nothing on film. We dicussed the merits of film vs the emerging digital technologies as I had bought my first watec in 2005 too. It was Ed who mentioned your page in our musings.
The methods are as old as they come, it’s the detector technology that has evolved quickly. I’m surprised myself how good the reults can be if fortune places a nice meteor in the field of view.
Looking forward to more!
Bill.
Hi,
Thanks. I’ve only had two really good spectra captured in the 2nd and 3rd orders (one of which appears as the background image for some of the info banners on the BAA page!) so they are rare catches. This one was particularly luck because the Geocentric velocity was low, at just a shade over 21 km/sec. This meant that all the atmospheric lines that light up with faster entries were subdued. That was the only reason it was possible to produce any reasonable plot.
I’m hoping to extend my system with another camera later in the year. Once I get a couple of representative results then I’ll put something together for the Journal.
In the meantime a quick summary will be in the next(?) TA mag.
Cheers,
Bill.Hi,
Returning to the fireball, Jamie has produced some graphics of the ground track and trajectory.I’ve added a “B” at my approximate location to show where the spectrum was captured from.
Thanks to all the GMN observers!
Cheers,
Bill.Hi Richard,
I knew I had a recent spectrum from my HiReMS II system that had a comparable bit of Near IR spectrum.I have been lazy and just cropped the image rather than fully process it… but the pic spans the spectrum plots of fig 2 in in the paper (it just squeaks into the third…)
The main lines are easily identifiable.
Who needs the VLT….! ; – )))
Cheers,
Bill.Attachments:
Hi.
It’s interesting you mention that paper in particular… I’ve used the spectra presented in that paper as a calibration starting point for many of my own!
I think elsewhere in my forum posts I actually show a comparison between my own set up, at the time, and the VLT one.Whilst mine was a lucky capture to be sure, the VLT one, given the field of view and size of slit was freaky lucky!
Bill.
Hi,
It looks like a sporadic in a low inclination orbit originating in the main asteroid belt.
Jamie produced some excellent analysis on the orbit and dark flight using multiple GMN cameras. I’ve sent these to Tracie for inclusion in the next TA.
Cheers,
Bill.Hi,
If one clicks on the file name part it downloads, or if one clicks on the actual image bit it opens in the browser.
However, yes, I think the previous method of embedding the images was somewhat better when reading/viewing a post overall, rather than having to view the images all separately.
Cheers,
Bill.Hi,
That’s great Alex.Considering that once anything glows, it’ll give off a “spectrum”, I wonder just how much the entry conditions affect the spectrum as I record it?
In real life so many variables and assumptions come into play. There’s a huge amount of theoretical work out there but as far as I can tell it still just boils down to observing and seeing what we get under any given conditions!Certainly the ones that seem to crumble away at lower speeds are fascinating. This is the project that the old WATECS, I mentioned elsewhere, will be turned to…. eventually.
Bill.
Just for a clarification. The first three images have the time as 0119, this is BST. Last image is 0019 UT.
I caught a very similar meteor in 2019. Video is here https://youtu.be/XLveGtJsvk4?si=wDjZ9dKAGo6ymLf1
The one from this morning exhibited the same ablation/disintegration.
The resolution of this mornings one is significantly better but the spectral type/form are the same.
Whatever the mineralogy, the large sodium signal seems to indicate a particular meteor behaviour.
Another little insight into things…
Cheers,
Bill.Hi,
I’ve never tried it but there is even a “sonification” option in VisualSpec…. might give it a go on one of my meteor spectra…
I imagine the solar sounds would have included some vlf recordings. To me these are the ultimate in “sound” observations.
In a similar vein to being in the midst of a solar storm, this recording I made about 10 years ago gives the impression of listening to an enormous number of birds chirping and screeching.https://youtu.be/L9WHaUxfKAM?feature=shared
It’s remarkable what’s there in the audio spectrum.
Cheers,
Bill.Here are a couple of videos from a security type camera (tilted upwards) 5 second interval between grabs. The dimmer colour is actually a lot more realistic than in the still pics plus it shows the motions…
https://youtu.be/beqT7Oabz_0?feature=shared
https://youtu.be/ncklGfjXi5U?feature=shared
Bill.
Hi,
Glad it went well, I had hoped to make it up but spent the day in bed recovering from the night before LOL, after a quick look through the images and videos as well as monitoring the radio I didn’t get to bed until about 9am!
The aurora was going all sky full tilt as the dawn encroached. Then there was the radio activity.
The aurora was reflecting signals from 28MHz all the way through to 432MHz, quite astonishing!Cheers,
Bill.…a little after thought…
What was really cool was the fact there was a corona aurora boeralis IN corona boreralis! LOL : – )))
Hi,
I was astonished to see the first activity as a lovely arc, grey green in colour to my SOUTH. spanned from SE through S to SW and was below Arcturus (“see aurora in south” image). After around 20mins the first sub-storm arrived and the coronal display pointing at Arcturus was remarkable.It just went manic for around another 20min before breaking up. Another sub-storm began to form at ~0100BST and the process repeated. There was just the faintest hints of both red and purple in places. Although these came out dramatically in the images. The motion was easily seen as it moved over head.
It was still going as the sky brightened. A complete whole sky display from twilight to twilight…. the stuff of legend.I have never seen such purple colouration so extensively before. A combination of incoming particle energy and enhancement from sunlight via fluorescence scattering from N in the upper part of the aurora. I wonder what it would have looked like in a “darker” part of the year…?
Certainly the best I’ve seen, since the big two night aurora in OCT 2003 and Nov 1979.
Lets hope there’s more to come!
cheers,
Bill.
