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Moon Imaging Tests for HST-Moon Transit, Critter Visitor

Posted: 25 September 2015

Open: Thursday, 24 September 2015, 1805 MST
Temperature: 95°F
Session: 860
Conditions: Clear

1813 MST: viewed the waxing gibbous Moon, 83X.

A transit of the Moon by the Hubble Space Telescope (HST) is predicted to occur Friday evening shortly after sunset. The conditions will not be ideal for imaging through the 8" LX200-ACF telescope in the observatory. This photo from Thursday shows the Moon just barely out of the tree to the southeast:


The Moon will be even lower 24 hours later, just barely above the hill to the southeast and definitely behind the tree. However, I will still try to image it.

The is how CalSky predicts the transit to look for my location:


I want some magnification on the HST transit image so I first tested imaging the Moon at prime focus + 2X PowerMate (1/400sec, ISO 640):


Since I would be doing an HD video recording using 60 fps at a crop factor of 1.3X, I switched to video recording at 1/60sec, ISO 400. This is one frame from the video:


However, I worried that was too much magnification and might not capture the HST if the calculation was slightly off. I removed the 2X PowerMate and did another video recording, one frame of which is here:


That magnification should provide good coverage of the transit.

I added a focal reducer for this full-disk image of the waxing gibbous Moon, 1/400sec, ISO 400:


I then did some lunar observing, 166X. Some fascinating shadows were visible along the terminator.

1906 MST: took a quick look at Saturn, low in the southwestern sky, 83X.

As I was closing up the observatory for the night, my guest from the previous night made another appearance:

Click or tap on image for larger version

If you are a fan of spiders be certain to click the photograph above.

Close: Thursday, 24 September 2015, 1920 MST
Temperature: 79°F
Session Length: 1h 15m
Conditions: Clear

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