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Will Tirion also drew a set of star charts specifically for the BAA, which we published in the 1980s. I covered mine in adhesive plastic and hung them up in my observatory – where they still are (well actually transferred to the warm room now, and rather yellowed). I’m thinking that due to this connection with the BAA, at least, the BAA should officially mark his passing, probably in the Journal.
The fact that it is Orion Telescope & Binocular as well is bad. These names disappearing would mean a significant contraction in choice in the amateur equipment market. But Meade has gone bankrupt before and then been rescued. We’ll have to see.
So they have not been re-named, according to the document linked to by Nick.
If, even, the IAU or any other authority could be considered to have the ability to rename natural objects whose names have been in literature and common parlance for centuries.
This has certainly long been John Roger’s view, that Cassini’s spot was not the current one. 19th Century drawings and early photographs show the GRS as a huge pale area at that time, unlike Cassini’s more concentrated dark spot. It seems likely Cassini was seeing a late stage of a contracting, darkening and accelerating spot, just as we are now seeing the similar late phase of the 19th C GRS.
Yes the BAA does have Mary Ashley’s notebooks in its archives. To look at these you would have to speak to the archivists: see the inside back page of the Journal for their contact details. I’ll also message you privately about this.
David Arditti (President)
Glad to have you with us, please allow me to welcome you to the Association, Robert.
You may be interested to know that we will be discussing the future of the Mills Observatory at the next BAA Council meeting.
David (President)
The discussion on this subject by Simon Banton, who I think works for English Heritage on Stonehenge, at the Winchester Weekend, was really interesting as well. A pity it was not recorded. Afterwards I discussed his views with him, comparing his take with that of Prof. Clive Ruggles, who is much more sceptical of some of the claimed predictive purposes of Stonehenge in relation to the movements of the Sun and Moon. Banton takes the view that the builders of these monuments understood quite a lot of astronomy, and has reasonable arguments to back this up.
I’ve encountered this problem of the trains on the West Coast Main Line on Sunday as well, Mike. It means I’ll have to travel back to London using a complicated route via Edinburgh, walking between the two Glasgow stations.
This doesn’t help you however; you may have to use the dreaded rail replacement buses.
David
There are always going to be clashes like that if we organise anything at a weekend, Jack. There are only 52 weekends in a year.
Embedding the video didn’t work very well because of portrait orientation; better seen on Facebook:
https://fb.watch/rt_1gKyFZL/Capturing nebulosity requires low focal ratio. To get optimal correction of chromatic aberration and coma at low focal ratios requires more lens elements. Yes you can use an ED (or similar) doublet with a coma corrector, but that’s 4 lens elements in total, and in most cases it won’t be as optimal as it could be, and there’s likely to be spacing errors, so better really, if you know the telescope will be used for imaging at this focal ratio, to build it all into one optimised, correctly measured-up tube assembly. Many people wish to use the dual-band, tri-band and quad-band filters for one-shot imaging, so chromatic aberration will still be a moot point.
It’s an interesting subject. There is a Moon Treaty to which the UK is a signatory, but it is a product of Cold War thinking, in that only bans nation states from claiming ownership of the Moon or parts of it, it does not prevent businesses based in those states from exploiting the Moon. How can you exploit something you do not own? It is a situation analogous to that with the deep oceans, which are not owned by states, but can be exploited. However there is an international mechanism to regulate that (not without controversy). There is no mechanism at all for the Moon.
This is all a rather different subject to light pollution, however, which is a fairly local issue, within the remit of national and local governments to deal with, if they care.
Incidentally, I don’t think it is a good idea to have a thread in the forum called ‘General’. Threads should be specific to the topics they are concerned with. What you have tried to do here is create a thread for what should be a forum sub-category. I don’t know if we actually can have sub-categories in this forum though.
And researching this topic led me to this fascinating lecture on the use of optical instruments by renaissance painters, very relevant to my talks (Presidential addresses) on the history of the telescope.
Interesting. I’m with James. I think it is a glass object that has been painted, and the painting has been finished, but I doubt it is a telescope. There are various geometrical, navigational and surveying instruments scattered round the room. I think the object in question could be a spirit level, with metal end sections and a short central glass section containing the liquid, through which we see the monkey’s arm. Such a level would be an important tool for a painter drawing horizons and buildings. Unlike a builders’ level, you might not make it with a flat base, as there would be no reason to do so.
They would be very complicated!
If the moons lined up, you would get big tides; if they were at 90º (2 moons) or 60º (3 moons), the tides would partially cancel out. But of course it would also depend on the masses of the moons and their distances from the Earth.
If the Earth had several moons they would probably be in resonant orbits, like those of Jupiter, with specific ratios between the orbital periods. Therefore there would be a certain period after which the same configuration would recur, and so would the same tidal conditions.
Yes, the basis of Conrad’s novel ‘The Secret Agent’, in which the author imagines an elaborate background plot to this event, linked to the Russians (who seem to be permanent bogey-men of espionage and terror in the British imagination).
