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Nick,
SharpCap’s pola alignment display was giving error values between 8″ and 15″ as I finished tightening my azimuth and elevation locks. This included a correction for the refracted pole at my latitude. The ambient temperature was around 10 C. Of course, tapping and nudging the mount / ‘scope showed how these values could change.
I fully expect it would give different values if I was to test it on a frequent basis. I don’t do long-exposure astrophotography and I’m not chasing professional observatory alignment standards, just content that it’s reasonably well polar aligned and is doing the job of finding my 30′ star fields.
Alex.
Thanks Paul,
‘Radio astronomy’ was a tongue in cheek comment in case anyone despairs of such laser displays becoming more frequent and disrupting our observing programmes.
Cheers,
Alex.
Thanks Robin.
Coming to a city near you… argh!!!
Clear skies – or – how do I take up radio astronomy…?
Alex.
Beam me up, Scotty!
It’s only a temporary art display, but at least Members are aware of it in case it tours the country to ‘delight’ you all. 🙂
Alex.
Hi Stan,
This object was captured on a few cameras in the NEMETODE video meteor network (UKMON is an independent network based in southern England) and here’s the provisional results from our data recorded by Steve Bosley (Clanfield), Peter Carson (Leigh_on_Sea), Nick James (Chelmsford), myself in Leeds and Jim Rowe (East Barnet). This is its ground track as it travelled from NE to SW (observers in continental Europe recorded the earlier phase of its flyby), e.g. see https://groups.io/g/globalmeteornetwork/message/1366
The mini-plots show it increasing in altitude and slightly decelerating as it crossed over England. (Its absolute mag. of around -2.7 is the magnitude of a meteor at a standardised altitude of 100 km in the observer’s zenith).
Our radiant plot, given below, suggests it might have been a Daytime gamma Virginid (GVI), although that shower is not in the Established List in the IAU MDC.
We obtained a well-defined solar system orbit for the body. The elements have some similarities with a GVI but not fully, perhaps it was a sporadic object. The orbit diagram is here
Analysis of the end phase suggests the object had climbed to 110 km altitude and was slightly accelerating as it faded beyond detection of our video cameras (when it was moving towards the Severn Estuary). At this altitude the meteor would be leaving the ablation layer. So, we surmise that it had a close encounter with Earth and has lived to tell the tale!
Such events aren’t uncommon and at the 2018 Winchester Weekend I described the Earth grazer of 2016 July 16 which took 10s to travel 470 km from the North East to the South coast.
Clear skies,
Alex.
As the first interview got underway I wondered if the team had made their discovery using a Sky-Watcher Infinity 76 ‘scope…? 🙂
Alex.
Thanks Bill.
Looking at the weather forecast it might be more profitable to listen to your radio system or tune in to the Radio Detection Livestream.
Cheers,
Alex.
Hi Jeremy,
It wouldn’t be possible to process such a large volume of unrecorded VS observations without the tenacious commitment of these Section members. I’m aware of cases where valuable observations have been lost after members passed away, e.g. by a house clearance or by wiping their computer drives. Thankfully, Melvyn’s family gave us full access to his extensive hoard.
As I mentioned in VSS Circular 180, the BAA Memoirs contain some useful VS data, but perhaps like in the English Mechanic not all salient information is to hand. Yes, they are certainly worthwhile and rewarding projects to search for old observations and add them to the Association’s archives and databases.
I’ve promised Roger I’ll write an update for the December VSS Circular.
Alex.
Hi David,
Here’s an online article with pics taken from Whitley Bay…
I had to laugh when they wrote “Dr Robert Massey, from the Royal Astrological Society…” 🙂
Clear skies,
Alex.
Hi John,
Have a look at
http://www.theastronomer.org/post/MeteorDiary/
https://www.imo.net/files/meteor-shower/cal2020.pdf
http://www.astro.amu.edu.pl/~jopek/MDC2007/
Cheers,
Alex.
Hi Dominic,
As William commented, my lenses also have a grub screw to secure the focus of the lens. As you’ll have experienced, focussing is quite a delicate operation with most video camera/lens combinations.
My Leeds_SE camera sometimes drifts out of focus during the seasons. Often this is an acceptable amount of soft focus, then just as I’m about to shin up the drainpipe it moves back into hard focus again.
I haven’t tried the masking tape technique. I suspected its expansion and contraction might cause some focus shift. I suppose it depends on the tightness of the rotating bezel.
Cheers,
Alex.
Thanks Jeremy,
I can confirm it plays very well from there and Members will find the presentation and discussion most interesting.
Clear skies,
Alex/
Unlike previous weeks, this evening I cannot view the talk (Jeremy’s) on the YouTube feed. It is working OK for Zoom users. Is it working OK for other YouTube watchers?
Alex.
Hi Ray,
I found that instead of directly clicking on an option I did right-click and selected Open a new window. This solved my Groundhog Day login problem.
Cheers,
Alex.
I tried to edit my latest entry on my Member’s Page to update the image. On clicking ‘Edit this observation’ – ‘Remove’ I got the error message
Clear skies,
Alex.
Gordon was most helpful when I researched HMNAO’s Occultation Machine. I occasionally ‘phoned him to update him on current developments in occultation astronomy and the promise of Gaia’s astrometry.Gordon’s autobiography was published in JOA 2016-4An obituary (written by Tim Haymes) will appear in the Journal.
Alex.
My Leeds_SE video meteor camera picked up some of these peskies, one clip had 5 of them traipsing across the sky.I see that ‘improvements to mitigate the impact on astronomers’ weren’t evident last night. Hopefully the satellites will be fainter when they attain their final orbits.The Heavens Above website FAQ says:“The brightness of a spacecraft is influenced by several factors…our magnitude estimates should only be treated as a rough guide, and the actual brightness you see could be considerably more or less than this”‘Enjoy’ the show!Alex.Hi James,
Issue 2014-04 of the Journal for Occultation Astronomy (pp. 13-22) contains an article by Friedhelm Dorst on ‘Observations of Planets and Stars near the Sun’.
We deliberated for some time before deciding to publish it in JOA. We do not condone any attempts to carry out such observations. Observing near the Sun carries high risk to one’s eyesight. It only needs to go wrong once! Even if an observer uses electronic recording techniques, they can be tempted to cast a naked eye glimpse towards the Sun and incur dazzle.
Be careful out there.
Clear skies,
Alex.
