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Sunrise at Crater Aristoteles

Posted: 11 October 2013

Wednesday, 9 October, was windy and then cloudy as a storm moved in. The sky cleared Thursday afternoon, 10 October 2013, and the observatory was opened at 1809 MST, 67°F. The sky was mostly clear. At 1814 MST, viewed Mercury, 83X. That was followed by Saturn, and then Venus. Slewed to the moon and using 206X, I began looking for a crater along the terminator that would show good shadow movement as the sun rose higher in the lunar sky. I finally decided on photographing crater Aristoteles in the northern portion of the terminator. Seeing was not very good, and in fact, at times during the next several hours, it was rather lousy.

I mounted the D7000 DSLR at prime focus of the 8" LX200-ACF using a 3X TeleXtender. At 1831 MST, I took this photo, 1/200sec, ISO 3200, showing Aristoteles in the center:


Every 30 minutes from 1835 MST to 2135 MST I did 30 second HD video recordings, all at 1/200sec, ISO 3200, except for the final one which was done at 1/250sec, ISO 5000 due to the moon's low altitude. The best frame from each movie was saved, the images cropped, and then combined to make this animated GIF showng sunrise at crater Aristoteles over a 3 hour period:


The image quality is not very good but you can see the shadow moving across the crater floor.

Two other lunar shadow videos done in October 2010 are on the Videos page. I plan to do more such videos this lunar cycle.

In between doing the images of the moon this night, I used the nightscope for some terrestrial viewing. At 2123 MST, I heard some "snorting" near the observatory. Using the nightscope, I located the Javelina that was exploring nearby.

I took my last look at the moon at 2145 MST, 83X, and then began closing up. Seeing was not good and the humidity was high.

The observatory was closed at 2200 MST, 50°F, humidity 47%.

Comments are welcome; use the Comments section below, or you can Email Me. Thanks.

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