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Star Count


keef_uk

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I did this from my back garden and got between 22 - 28. I live in Norfolk and have seen the sky darker and clearer than it was last night!

I need to move up the coast a bit, I've heard about that sky in Norfolk. Only 5 from Ipswich.

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I'm in a completely different place but I was also doing some NELM estimation last night. Besides looking for the fainter stars in Orion, I count the Pleides. With the naked eye, there's the two parents, and often four of the seven sisters are visible. If the fifth sister (seven stars) is visible, you've got about NELM of 5. If your eyes have trouble resolving the stars, you can use binocular or finderscope and calculate the advantage out to get NELM.

I found there's a narrow area about 20 feet across in my backyard that is quite good, perhaps 4.5 and that the field outside my neighborhood is only slightly better. I previously thought it was much better because of the distance from the streetlights. To get much better, I have to drive about 3 miles out of town. There I have perhaps NELM 5.5 or better. I didn't really give my eyes time to dark adapt. Had I done so, the limiting magnitudes might have been 1 more but my purpose was simply to compare sites available to me.

A 10 inch scope in my backyard would show fainter objects than a reasonably portable scope half that aperture or less. However, I would much rather spend time with an awesome naked eye view and little or no scope than I would with a massive scope and little to see with the naked eye.

Fortunately, my town is in the process of replacing "cobra" head HPS streetlights with down-focused metal halide fixtures. The nearest city (20 miles away) is switching out their HPS lights to LED fixtures. They're probably less than 10% complete and it will take years before it's all switched over because they're not replacing them until there's a failure or a remodel of some sort where they widen lanes or redesign an intersection.

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The seeing was a bit "unstable" here this evening (west Somerset, on the edge of Exmoor), but I definitely counted 22, possibly 23. I'd guess the limiting magnitude was somewhere between 5.5 and 5.75.

James

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By the way you are supposed to include the three belt stars.

Just re-read the web page ... oops ... so it should

Oh well, I guess it is better to record too few stars than too many, and I could only see the belt stars when I wasn't hiding behind the telegraph pole, so I suppose it evens itself out ... i hope

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I could see 3 stars ..... and that included the belt stars :)

If you want an idea of how bad my sky is, set the light pollution level on Stellarium too the highest setting of 9 and then imagine the sky worse than that.

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