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Hi,
Being away from home over the new year I was unable to do any spectroscopy. Given the weather I don’t think that would have been very successful anyway… ; – )
I did, however, attempt some visual observing from where I was, just outside Dundee, and for a brief spell I thought is was going to hold. Alas, no but I did see 2 Qua’s and 1 Spo in just under an hour. Nice to see the real thing from time to time…
My radio system kept vigil on my behalf and I was surprised to see that in terms of the maximum meteor count this years QUA’s pipped the 2019 GEM’s for the highest rate. 156 QUA’s 04-05UT verse’s 143 GEM’s also 04-05UT. Of course the GEM rate is pretty high over a much longer period…
I’ll put together some graphs at some point but it looks like it would have been a nice show given some clear skies.
cheers,
Bill.
Hi,
I’m not sure what happened to the original picture so here’s another version in case anyone wants a look…
This is the original orientation and full size from HD frame. It also has been contrast stretched to show the faint lines.
Even though it looks like I only got the start of the meteor, it’s just brilliant!
Cheers,
Bill.
Hi,
Thanks and thanks for the kind offer Jack. I’ve got a pdf copy (from the NIST site) of the Multiplet Tables. These “old” works are invaluable even today!
I generally use a selection from the NIST persistent lines catalogue. This has proved an excellent source of data for meteor stuff. Although I don’t think I’ll ever get to needing 0.0001A resolution on my spectra, but you never know LOL! : – )))
cheers,
Bill.
PS. Given I’ve found some other metals I suppose I should change the topic title to “Mostly” iron meteor spectrum… ; – )
Hi All,
After tweeting a re-worked spectrum it seems the meteor was captured on an all sky system (Jamie in Lochearnhead). He estimates it was -3.
I decided to re-work the spectrum as I hadn’t really paid much attention to the “thermal tail” between 550nm and 650nm. With the increased resolution I now have I’m more confident about identifying more exotic lines.
It looks like there are some weak lines from Tungsten, Vanadium and Manganese in the mix! I’m pretty sure there’ll be Nickel in the meteoroid but these tend to have their strongest emission in the deeper UV, just beyond my detection limit.
This one really was a cracker and a step forward in observation capability. There are some older observations claiming up to 70 lines in a spectrum but that was based on a spectrum that actually had 27 native lines in the image. The assumption was that the other lines were there because they had emissions at particular wavelengths and were blended together. Using that method and modern data I could claim well over 100 lines here, but I’m not sure if that is really honest science. Anyway, from my element list I count 60 native lines in this spectrum without any assumptions of blending.
cheers,
Bill.
An awful lot of variables so strictly “order of magnitude” (the physicists get out of jail free card!) number…
The column diameter of the train is ~ 30 to 50m. Remarkable to consider that the meteoroid itself might only have been a couple of mm in diameter. The atoms evaporate off at a few km/sec but bump into the atmospheric atoms after a few free path lengths, a few metres then diffuse into the atmosphere over however long depending on size, mass, density, composition, velocity etc etc.
Most of those we have little or no idea about…!
Cheers,
Bill.
What was the scope/camera (pixels and pix size)/exposure you used? Could you send me the raw frame of the second shot?
Just curious to see if I can make some measurements….
cheers,
Bill
Lucky catch!, Certainly does look like a faint wind distorted train in the second field.
So I’m going to say, probably… ; – )
Ahhhh the road to hell is paved with good intentions….
Well almost, must be 12 years ago I had the balloon, the helium and the instrument…
I must confess not for meteors though, part of a student project that both literally and metaphorically never got off the ground! Could never get the remote control and radio data link to work properly. It was going to be looking at cosmic rays but I thought it would be a great idea to fly it at night with a camera just out of curiosity. Bounced due to health and safety concerns… ; – (
…and the nice big meteorological balloon perished without ever being inflated…
Somebody will do it with a Pi and an IMX camera!
… and looking at the RMOB site it looks like my radio system hung yesterday!
also bl**dy typical! ; – ((
Hi,
The weather’s not looking so good here either but I may put out a couple of spectro-camera’s just in case.
That would be an interesting catch…
Cheers,
Bill.
HI,
Sounds great! The lines I’ve got from the NIST site indicate the Cobalt and Nickel lines are just out of reach in the UV for my system.
Titanium and Vanadium have been reported in meteor spectra but I’ve never conclusively ID’d those elements. It might be possible now I’ve got to this level of resolution and sensitivity!
Cheers,
Bill.
Dear oh Dear, just as well I said “some” certainty….!
I’ve been studying the original image very closely and what I thought might have been faint second order lines appear to be in fact some of the very lines I thought were not present. There is the faintest hint of the 777.4nm O line. So it was “probably” traveling at a lowish Vg!
Always be skeptical, LOL!
I’m giving myself a headache!!!
By trying to figure out what it can’t be (in terms of “normal” meteor lines) I’m down to around 150 lines from and handful of metal elements (non Fe neutral and ions) plus around 100 main Fe lines.
Still seems kinda uphill… ; – )
Hi,
I Initially thought the line to the right were a second order also but I’m not sure. Careful examination reveals the separations don’t quite tie up with twice the wavelength even correcting for the slight non linearity of the dispersion.
Checking through the NIST data base there are over 2000 Fe lines listed from 350-450nm. Looking at the “stronger” ones I still can’t get a clean fit.
I’m sure I’m imposing am image scale bias, as this one is very large for a meteor spectrum. 35mm focal length is positively a telephoto lens in the meteor observing world.
I’ve chopped the spectrum into shorter sections from a single 45ms slice (it looks quite different when examined this way, a curious psychological effect.)
It may or may not help….! ; – )
Yep, that’s correct. near UV towards left hand side and the whole thing is an emission spectrum.
Based on the sensitivity profile from other spectra, the wavelength span is around 360-650nm (ish!)
Continual failure with the usual elements in meteors is making me more convinced it is some sort of man made “stuff” re-entering.
No luck with an orbit so far, as that would at least help resolve the natural/man made issue.
However, if it is an artificial source there are not that many spectra of what’s coming back in so it’s still interesting in it’s own right!
Hi,
Yes, I’ve tried all of these approaches and I still don’t get anything I can make sense of. Checking against several cometary spectra was the first port of call since it doesn’t match any meteor spectrum I’ve caught. In the 11 years I’ve been actively pursuing the video operations I’ve had one other like this. That has just been put in the “unknown” category.
I’ve got a few more strategy’s to apply first. I’ll figure it out eventually… maybe! ; – )
Cheers,
Bill.
Indeed, LOL!!! ; – ))
Been leafing through my optoelectronic texts. The cut of a si photodiode can be as low as 320nm but the glass will probably attenuate that heavily. I’m thinking the shortest wavelength have got to be of the order of 350nm.
I think I can see some pattern of Fe lines at the extreme left BUT if that’s correct then there is nothing at the usual Ca wavelength. So it would need to be a pure Fe/Ni. Problem with that is I have never seen such diffuse bands before. This is usually the sign of multiple electronic bands overlapping from molecules.
Something to do on the weekend if it’s raining I suppose….
cheers,
Bill.
