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Crescent Moon, Mare Smythii

Posted: 20 May 2015

Monday, 18 May 2015, started out clear but unforecasted clouds arrived mid-day, with the sky overcast by mid-afternoon. As sunset approached, a surprise brief rainshower occurred. It only dropped 0.004" of rain. The sky dawned clear on Tuesday, 19 May, and stayed mostly clear.

Open: Tuesday, 19 May 2015, 1812 MST
Temperature: 86°F
Session: 822
Conditions: Clear, some clouds low in west

1821 MST: viewed Venus, 83X. Then tried for Mercury, low in the western sky and a thin crescent phase. No joy. Slewed to the crescent Moon, about 45 hours old. It was visible in the 7x50 finderscope and was faintly visible at 83X, with sunset still about an hour away. Grabbed this handheld iPhone 5s afocal 83X photograph:


1835 MST: slewed back to Mercury; still no joy. 1842 MST: no joy on Mercury. I had seen it two evenings prior at 1842 MST, but of course, it would be lower and a thinner crescent this night against a slightly brighter sky. 1850 MST: still no joy on Mercury.

Since I planned to do some extensive imaging of Saturn this night and would have time between imaging, I decided to set up my recliner on the observatory so I could do some 12x70 binoculars sky observing:


1907 MST: some clouds becoming more obvious in the southwest to west. Still no joy on Mercury. 1921 MST: sunset. Still no Mercury and it would now be into a tree. Slewed to the Moon.

Mounted the D7200 DSLR at prime focus of the 8" LX200-ACF and took this photo, 1/400sec, ISO 1600:


1932 MST: began doing lunar observing, 222X. I noticed that the far wall of Mare Smythii on the lunar limb was nicely visible. Took this handheld iPhone 5s photo (cropped) showing Mare Smythii and its far wall:


1947 MST: seeing was deteriorating, so switched to 83X for lunar observing.

1951 MST: took this handheld iPhone 5s photo of the western sky using NightCap Pro, showing Jupiter, Venus, and the crescent Moon:

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1955 MST: more clouds in the southwestern sky. Viewed Jupiter at 83X and 222X. Three moons were visible. Seeing was not very good. 2011 MST: more clouds in the southern sky now. I began to wonder if I would have to cancel my Saturn imaging plans. 2014 MST: took this handheld iPhone 5s photo (cropped), afocal 222X, showing three Jovian moons (Jupiter is overexposed):


2027 MST: clouds in the southwest seemed to be thicker. There were also clouds in the northwestern sky now. 2038 MST: Saturn rose over the hill to the southeast but was still in a tree. Clouds were now in most of the southern half of the sky. 2043 MST: took a quick look at Saturn through the tree branches, 222X, but it was a lousy view. Decided that the clouds would indeed mess up my plans for Saturn imaging so I began closing up for the night. I will do the Saturn imaging on another session.

Close: Tuesday, 19 May 2015, 2106 MST
Temperature: 62°F

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