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I wonder what the distribution of different crater forms on the Moon’s surface tells us about the frequency and intensity of strikes? Is it assumed that the direction and intensity is randomly distributed? Does the actual distribution square with this? If not, what does it tell us about how the distribution we see to day was formed?
Hand-holding a phone can be mighty frustrating. I tried it for a while and obtained a few decent shot but mostly not.
So I invested in an Altair Universal Cell Phone Adapter which makes it very much easier. A bit pricey – but better than the cheaper versions (yes, I tried those too!). Here’s an example of the result with a Samsung Galaxy S5 phone.
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Alan (Warrington)
Michael
See here (a BAA member I think):
http://www.threehillsobservatory.co.uk/astro/radio_astronomy/radio_astronomy_1.htm
Alan
That’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!
Naked 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.
Many thanks, Robin, for the clarification on the data series. I never thought variable stars were that interesting – but I’m beginning to wonder now!
I 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)
I 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?
I 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.
