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Monsoon Weather Pattern Continues,
Visitors, Moon-Venus-Jupiter after Sunset

Posted: 20 July 2015

At the start of my previous session on Friday, 11 July, I discovered that my old (1961) Edmund Scientific 3" Newtonian reflector telescope was badly out of collimation. I made an attempt to recollimate it during the day on Saturday, 11 July. While the primary mirror would easily move to correct the collimation, the problem definitely seemed to be with the diagonal mirror not being exactly 45°. I made several attempts at repositioning the mirror but nothing seemed to get it precisely correct. A star test will be required to determine just how good or bad the collimation is now.

Saturday and Sunday nights, 11-12 July, were cloudy so I missed being able to take another Pluto image to confirm my earlier iPhone image of the planet. Had a brief monsoon thunderstorm Monday afternoon, 13 July, with lots of lightning/thunder and 0.42" of rain in about 30 minutes. More monsoon storms occurred Tuesday afternoon, 14 July, but only got 0.04" rain here, although there was a lot of lightning/thunder once again. One of Tuesday's storms apparently started this lightning-caused wildfire in the hills about 15 miles to the northwest of Oracle:

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And a view of the fire after sunset:


The fire was no threat here and appeared to be out by Wednesday morning, 15 July. Wednesday afternoon there was this nice monsoon season thunderstorm to the southwest of the observatory:


About an hour later the storm had moved a little northward:


It dropped a little rain here (0.05").

Thursday, 16 July, dawned mostly clear, but as is typical for southern Arizona monsoon season, the sky clouded up mid-day. A monsoon storm with lightning and rain came through after sunset, dropping 0.26" rain. Cloudy skies continued on Friday, 17 July, as moisture from what had been Pacific Hurricane Dolores made its way to Arizona. The rain arrived early and 0.15" was accumulated Friday morning. Heavy rain had been forecast for Friday night into Saturday, but it never showed up here. The sky continued to be cloudy on Saturday, 18 July, and Sunday, 19 July. Some rain occurred overnight (0.25").

Sunday morning had some sunshine and a small Gambel's Quail family came by the house for breakfast. There were six chicks running around with mom and dad. I managed to get five chicks in this photo with their mom:

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A little later mom and two chicks came onto the patio:

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Another brief storm dropped all of 0.01" of rain two hours before sunset on Sunday. But as sunset approached on Sunday the western sky cleared enough to get some photos of the crescent Moon, Venus, and Jupiter.

Sunset, with the crescent Moon at the upper left:


30 minutes later at 1959 MST, took this photo of the Moon, Venus, and fainter Jupiter to the right of Venus:


2002 MST: western sky with the crescent Moon, Venus, and Jupiter:

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Due to thicker clouds in most of the rest of the sky I did not open the observatory. All this cloudy weather has really messed up my observing and imaging plans. Hopefully a dry spell this week will provide some cloud-free skies.

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