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PostPosted: Wed Oct 24, 2018 9:41 pm 
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Joined: Thu Jun 02, 2016 11:32 am
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Location: New Farnley, Leeds lat 53.8N long 1.6W
2018 October 24, 20.55 – 21.10 UT. Halloween is approaching and the Summer Triangle is declining the cold autumn sky: it’s a good time to swing that neck-cricking double star chopper, the achromatic refractor, down onto Lyra. We’ve all done epsilon 1 and 2 to death but tonight the seeing is so poor (Pickering 2 to 4) that I cannot split either component with 90mm aperture at f10.
But, how about an easier victim? There’s another pair of pairs 7 or 8 degrees south-east of epsilon in Lyra, Struve 2470 and Struve 2474. Some trouble to call them the Double Double’s Double. There they are! Sparkling in and out of focus in the poor air, and separated by a little over 10 arc minutes these two pairs comfortably fit into my 60mm f10 aperture x60 field, and at x120 they are still a neat sight. Although each pair is vastly distant from the other and not physically associated, Struve 2470 and 2474 are 7th and 8th magnitude droplets, separated by 14 and 16 arc seconds respectively; and they share similar position angles. Broadening my blade to a full 90mm aperture makes the southerly pair, Struve 2474, bleed an ever so slightly warmer tinge. Save your neck and catch them now before they go west and bend themselves over the black block of the north horizon.
Happy Halloween! Bob


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PostPosted: Thu Oct 25, 2018 10:02 am 
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Joined: Thu Dec 20, 2007 11:41 am
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Location: Bruges (just over Channel)
"the Double Double’s Double" :lol:
There's also such a marvelous double-double not far from the Pleiades, 4° NW of it. Drive your scope roughly to RA 3h 31m and Dec. +27° 39'. Give it a go.

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Thanks to the clear cold nights...


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PostPosted: Thu Oct 25, 2018 10:41 am 
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Joined: Thu Jun 02, 2016 11:32 am
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Location: New Farnley, Leeds lat 53.8N long 1.6W
Hello Coldfieldboundary (can I call you "Dary" for short?),
Thanks, yes I'll chase that one up next time. It's a pair of Struve double stars, bizarrely designated STFA 7 and 401. Apparently the pairs are 10 arc minutes apart: STFA 7, magnitudes 7 and 8, separation 44 arc seconds; 401, both about 7th magnitude, separation 11 arc seconds.

Kind thoughts, Bob


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PostPosted: Sun Oct 28, 2018 8:35 pm 
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Joined: Thu Jun 02, 2016 11:32 am
Posts: 503
Location: New Farnley, Leeds lat 53.8N long 1.6W
After a few variable star estimates on the cold, dewy lawn, I had a chance to sweep up STFA 7 and 401 this evening, 2018 October 28 at 20.00UT. Using the twin mounted 80mm f5 refractor as a finder, the Pleiades swarmed into view at x16, then onto the double stars which were easily spotted in the 80mm, with STFA recognisably separated. They are an intriguing skewed pair of doubles in the 90mm x60 field. I wouldn't exactly call them a "double double" though, since they are an ill-matched set. The southern couple are neat white twins but the northerly ones (STFA 7) are a magnitude duller and four times further apart. Interesting game this double double hunting, like catching two butterflies in the same net. Kind thoughts, Bob


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