Forum Replies Created
-
Posts
-
2024 PT5 was mag 17 when discovered in southern skies and is currently mag 22 at high northerly declination, but next January it will reach mag 18, within reach of more amateur imagers (if the MPC and NASA Horizons ephemerides fully include the perturbations from its flyby).
Alex.
I’ll pass on a piece of sage advice from my old supervisor – don’t use Dr. on a flight ticket!
In my case I used it on a hotel booking in Scotland and had a waiter (at dinner) asking my opinion of his back problems. I advised him to see his GP!
When on holiday a GP I know tells people they’re a vet.
Alex.
Many congratulations Doc. Wilson!
You can now expect to be asked by visiting tradespersons (as I once was) for assistance with treating assorted ailments!!
AlanAlan, Andy,
Our late friend Dr Dave Gavine – who was awarded Scotland’s first Open University PhD for his thesis ‘Astronomy in Scotland 1745–1900’ – related the story of a visit to the National Gallery of Scotland during which his mobile phone started ringing. As a member of staff walked over to reprimand him, Dave commented “Apologies, I’m a doctor…” 🙂
Have fun with your title.
Alex.
One team of researchers predicted ‘January 2024’, so that’s been and gone. Whenever T CrB erupts, I predict that I will be clouded out for ~20 days whilst it fades back to mag 10, but the weather will relent during the secondary eruption.
Alex.
I’ve attached the September Newsletter from ESA’s NEO Coordination Centre which gives a summary of the detection and impact of the asteroid.
Alex.
Hi Tim,
Thanks for correcting the e-mail address, I quoted the one in the 2024 Handbook. The shared link works fine.
Alex.
Hi Robin,
Nice sharp images with a good limiting mag. I had variable cloud cover last night, but during the clearer intervals my Leeds_N caught faint examples of your bright auroral rays through the Plough.
Cheers,
Alex.
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.
Attachments:
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.
Attachments:
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.
