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Alan ThomasParticipant
Michael
See here (a BAA member I think):
http://www.threehillsobservatory.co.uk/astro/radio_astronomy/radio_astronomy_1.htm
Alan
Alan ThomasParticipantGreat idea, Peter. I’ll let you know when I have thought a Great Thought!
(don’t hold your breath)
Alan ThomasParticipantThat’s interesting, though the camera is more sensitive than the eye. I took a few shots myself and M is clearly visible.
Here’s a (possibly dodgy) hypothesis:
1. The current ‘lockdown’ has reduced the volume of pollutants in the atmosphere.
2. This has increased the effects of light pollution.
3. This will be especially significant in urban areas (such as here, between Manchester and Liverpool).
4. Ergo a) stars around the mag of Megrez will be pushed closer to the limits of naked-eye visibility. The effect on Megrez itself is especially noticeable because of its prominent location. b) this effect will be more visible from urban (heavily light polluted) sites than rural ones.
In principle, these implications appear to be amenable to test fairly easily.
However, this reasoning seems to imply (counter-intuitively) that atmospheric pollution reduces light pollution which improves seeing!
Alan ThomasParticipantI don’t know what’s going on, but it makes a change from coronavirus!
Alan ThomasParticipantNaked eye observation 22.50. Megrez barely visible with averted vision. The Plough is looking a bit like Trafalgar Square without Nelson. Of course it may be something or nothing – but it doesn’t look right.
Alan ThomasParticipantNaked eye observation 21.59. Megrez barely visible.
Alan ThomasParticipantNaked eye observation at 20.26. Megrez not visible.
Alan ThomasParticipantThanks Jeremy!
Alan ThomasParticipantThanks Andy!
Alan ThomasParticipantMany thanks, Robin, for the clarification on the data series. I never thought variable stars were that interesting – but I’m beginning to wonder now!
Alan ThomasParticipantI don’t know what the Ic V and B designations for the plots refer to, but do I detect a downward trend in the red plot – and an upward in the green? (this refers to Gary’s earlier post)
Alan ThomasParticipantHi Gary
I am not a variable star observer. How would you interpret these data?
Thanks
Alan
Alan ThomasParticipantI went out at 20.30 and again at 21.50. I could detect Megrez with the naked eye, but only just, a little more easily with averted vision. It certainly seems unusually faint – but is it?
Alan ThomasParticipantI had been out observing for a couple of hours earlier in the evening and was just having a final look around. So far as I can tell, the skies were perfectly clear. But I suppose a passing puff of cloud might be responsible. Or some other obstruction of course.
What surprised me was that Megrez was not simply faint but invisible, at least to the naked eye. That’s something I have never seen (or not seen) before in over 60 years of skywatching.
I will be having a closer look tonight with optical aid.
Alan ThomasParticipantThanks for those comments. So far I am reassured that I am not going nuts!
Alan
17 March 2020 at 4:53 pm in reply to: Emergency Motion add to Special Gen. Meeting / Ord. Meeting Agenda 25th March 2020 #582112Alan ThomasParticipantThis letter from John Goss, Past President of the Astronomical League, that appears in the current issue of SkyNews may be of interest.
Alan
Alan ThomasParticipantThanks, James. I’m hoping to see this when it comes to Oldham (not too far from where I live) later this week.
Alan
Alan ThomasParticipantDust does seem to be one possibility –
Alan
Alan ThomasParticipantSo that’s settled. Let’s hope the weather will calm down soon before we all go nuts!
2 January 2020 at 3:51 pm in reply to: BAA 2020: Highlighting Women in Astronomy From BAA President Alan Lorrain #581860Alan ThomasParticipantTwo interesting articles about two remarkable astronomers. Thanks!
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