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Hi Bill,
You might have read the attached paper which suggests that meteors with slow Vg can produce sodium-rich spectra, irrespective of the meteoroids’ chemical composition.
Alex.
I found this Seestar Spectroscopy presentation online (from minute 24 onwards)
https://www.youtube.com/live/4BhlkOqo8cU?t=619s
I don’t own a Seestar and I can’t comment / advise on the contents of the presentation. Perhaps you’ve already seen it.
Alex.
Hi Bill,
Re your ‘melting meteor’ from 2019. We have a match in the NEMETODE dataset – a 2-station capture by Andy McCrea (Bangor, N Ireland) and myself. It suggests a mag 0 sporadic, detected at 90 km altitude and extinguished about 10 km lower, with a 12 km ground track. Its Vg was about 18 km/s, so particularly slow.
Having looked at only a few examples of this nature, they had slow Vg and/or shallow angles of attack to the atmosphere.
Alex.
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It was quite a cloudy night but the meteor was recorded on my Leeds_N UFO Capture camera. UFO Analyser gave it a provisional single-station classification as a mag -0.6 alpha Capricornid, which are relatively slow meteors with a geocentric velocity of 23 km/s.
Alex.
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my copy of Star Atlas 2000.0
Apologies, I meant to write Sky Atlas 2000.0, but I can’t see an Edit option after posting, only Reply or Quote.
Alex.
This is very sad news. Almost every observer possesses a star atlas, chart or book illustration drawn by Wil Tirion. He was a great collaborator with Storm Dunlop on their night sky guides. As I write this note, my copy of Star Atlas 2000.0 is nearby, along with numerous other examples of his fine work. They enhanced our enjoyment of the night sky and continue to do so.
Alex.
Nicely recorded, Nick.
ESA’s July Newsletter (attached) gives a little more information about the asteroid.
Alex.
It looks like the weather over the next few nights will make it challenging to see the flyby. Fingers crossed.
To the best of my knowledge, NASA Horizons functions correctly, but I’m neither a distinguished engineer nor an expert witness. 🙂
Alex.
Hi Robin,
The paper and SPAD vs CMOS sensor performance are now being discussed on the IOTAoccultations forum
https://groups.io/g/IOTAoccultations/topic/recent_article_on_use_of/106850984
Cheers,
Alex.
Hi Robin,
The lead author gives their e-mail address, so you could contact them for clarification.
Fig. 4 shows interesting disparities in the ‘g’ and ‘r’ light curves during the ingress phase. These are the kind of features that the Leona-Betelgeuse analysts will be investigating.
Cheers,
Alex.
A paper on ‘Single-photon gig in Betelgeuse’s occultation’ is available on ArXiv
https://doi.org/10.48550/arXiv.2406.14704
(Thanks to Oliver Klös IOTA/ES for bringing this to our attention)
The authors describe recording the 2023 Dec 12 Leona-Betelgeuse occultation using a Single-Photon Avalanche Diode (SPAD) array, and they give their measures of the light drop and Betelgeuse’s angular diameter in the SDSS g-band.
(We await the paper(s) from the Leona-Betelgeuse pro-am campaign).
Alex.
I’ve visited The Mills several times and it’s very concerning that its future as an astronomical observatory is in doubt. I will add my support to the survey and petition.
Another favourite in Scotland was the City Observatory on Calton Hill, Edinburgh. Sadly, it fell int0o disrepair and the City of Edinburgh converted it into an Arty Farty Centre
https://www.collective-edinburgh.art/visit/site-history
https://www.astronomyedinburgh.org/about-us/a-guide-to-edinburghs-popular-observatory/
Alex.
Hi Mark,
I took the observations from the Mission 29P page, but it wasn’t straightforward, because some entries aren’t in chronological order and there’s also G, T and V estimates in there. I used the R mags but then the full set (2023 Aug – 2024 May) created a wav file much larger than the 4 MB file limit.
Anyway, a rough and ready wav file is attached, covering 29P from 2024 Jan 16 to May 18.
At the Greenock meeting Nick James suggested that Astronify provide a user-friendly interface, such as an online webpage, where users could upload a csv file containing ‘time’ and ‘flux’ data, and it would automatically generate the wav file. Additionally, users would be able to modify the median pitch, duration between notes, select log or linear flux, etc. A nice little project for someone with any spare time…
Cheers,
Alex.
Hi Callum,
Your audio really gives a strong impression of being in the midst of a solar storm! 🙂
Cheers,
Alex.
My next door neighbour to the SW is half a mile away but the lights on his daughter’s horse paddock illuminate my lounge! Thankfully they aren’t used too often, and earlier, not later. Everything you say matches my experience here. I’ve tried asking for lights to be adjusted etc but no-one gives a …
Cheers, Alan.
Alan S – Many neighbours are unaware that their external lighting is a nuisance. Having a pleasant chat with them can sometimes resolve the problem. The other year a neighbour a little distance away from me installed a light that would have been visible from the next county. It brightly illuminated my house, part of the garden and observatory. I reported it to the local council as ‘light trespass’, an official came out to assess the problem and asked the resident to adjust their lighting. They still have an external light, although it’s not as blazing as before. Not an ideal solution, but I didn’t want to aggravate any dispute, and it’s now partly masked by bushes and trees.
Note to report any issues as ‘light trespass’, not as ‘light pollution’, ‘loss of night sky’ and never mention ‘astronomy’. Unfortunately, in some circles amateur astronomers are viewed as ‘nutters’ and this can work against you. My jaundiced opinion, but born out of years combatting light pollution!
Cheers!
Alex.
Hi all,
I fully agree that it was a most enjoyable and informative meeting which continued the high standard set at the Greenock BAA Workshop on 2019 October 12
https://britastro.org/event/observers-workshop-solar-aurora-nlc-and-deep-sky
Because of my tickly cough I sat at the back where I could get a frequent drink of iced water. My location was advantageous, because when PS Waverley sounded her horn – quite apt for the day’s theme of ‘The Music of Space’ – like Nick I was able to rush to the window and record her departure
(Apologies to Dr Mackinnon whose talk was temporarily upstaged by a Paddle Steamer)
Alex.
Peter – that pic must have been taken on one of those rare rainy days at Ribblehead… 🙂
Gary – perhaps the Council would consider making the Weather Owl available via the BAA Shop… 🙂
Alex.
Generally poor observing conditions in NW Leeds since last autumn. I don’t expect much improvement until the weather systems stabilise. Visual observing can take advantage of breaks in the cloud cover but occultation timings require good conditions at a specific time window, hence very few successes this year. Variable star photometry and meteor cameras are hindered by variable sky transparency, RMS waits for 20 field stars whilst UFO Capture detects meteors under almost any conditions; still poor coverage of the major meteor showers.
The local council has replaced all streetlights with flat panel luminaires, but many residents are installing very bright (in)security ‘photon torpedoes’ to floodlight the sky, their brickwork, gardens and their neighbours’ property. They should be banned.
I’ve come to the conclusion that when the BBC or Met Office say “clear” they mean driving conditions for motorists, not sky clarity for astronomers. For those who don’t have £zillion weather forecasting supercomputers we rely on low budget solutions such as in the attachment. I also use Sat24 GB every evening to check the movement of the cloud formations.
Alex.
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This was good advice on ABC News, especially item 4…
Alex.
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