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Lunar Crater Stöfler, Critters, Star Occultation,
NGC7252 Atoms for Peace Galaxy

Posted: 12 September 2013

The observatory was opened Wednesday, 11 September 2013, at 1820 MST, 91°F. The sky was mostly clear. Viewed Venus, 83X and 222X, at 1828 MST. Then began observing the moon, 222X. Crater Stöfler at the terminator presented a nice view. Sunset occurred at 1838 MST. Saw a nice bright "green flash". I then took some HD video recordings of Crater Stöfler using the D7000 DSLR at prime focus + 3X TeleXtender. This is one frame (cropped) from a 1/30sec, ISO 1600, video:


I then noticed a visitor to the observatory:

(Click or tap the image to see a larger version.)

The spider was escorted out of the observatory.

At 1909 MST, I began some extended viewing of Crater Stöfler, 364X. Seeing was not great but at times the view was very good. Switched to 267X as seeing deteriorated. At 1925 MST, I did a tour over the moon, 267X.

At 1944 MST, I saw that the spider had returned and was near my shoulder as I was observing the moon. Terminated.

By 1957 MST, the shadows on the floor of Crater Shöfler were definitely shorter than they had been an hour before. It is always fun watching changes shadows along the lunar terminator. At 2003 MST, seeing was really bad and I switched to 83X. I noticed a bright star about to be occulted (maybe) by the Earthlit side of the moon. Switched to 222X to watch the occultation. There were actually two stars visible; one faint and one brighter. By 2020 MST, it looked like both stars would be a near miss. Using 364X, I watched both stars as they passed "over" the lunar south pole.

Returned to using 83X and saw more stars that would definitely be occulted by the moon, one of which was bright. I set up to photograph a sequence as the moon approached the brightest star. These images are 1 second, ISO 100; 1/5sec, ISO 400; and 1/5sec, ISO 400, respectively:




The star was occulted at 2037 MST. I did not identify the stars that were occulted. Took my last look at the moon, 83X, at 2048 MST.

Slewed to NGC7252, the "Atoms for Peace" galaxy. It was faintly visible at 83X using averted vision. I planned to image it once the moon was no longer a factor. By 2142 MST, with the moon getting lower in the west, the galaxy was somewhat easier to view, but it was still a "faint fuzzy blob". At 2230 MST, I began setting up for prime focus imaging of the galaxy. Mounted the D7000 DSLR at prime focus of the 8" LX200-ACF using the off-axis guider. Did a focus test on the star Fomalhaut using a Bahtinov Mask. I used the AutoStar "High Precision" mode to GOTO NGC7252. It first slewed to Fomalhaut, which I centered in the camera FOV. The telescope then slewed to NGC7252. A good guide star was in the illuminated reticle eyepiece field-of-view. At 2300 MST, I did a 10 minute, ISO 6400, guided exposure, with this (slightly cropped) result:


I completed imaging at 2311 MST and removed the camera from the telescope. At that point I heard a large animal near the observatory. It was snorting and sounded like it was eating something. A few minutes later I heard it walk past the observatory but I didn't see it. I decided that I will put my "night scope" in the observatory for use in similar situations in the future.

At 2336 MST, viewed the M74 galaxy, 83X. Supernova SN2013ej was still visible.

I then viewed M45 (Pleiades), 83X. Some nebulosity was visible around the bright stars.

Beginning at 2349 MST, I did a tour of Deep Sky Objects (DSOs) in the constellation of Aquarius, 83X: M72 (globular cluster), M73 (open cluster), NGC7009 (Saturn Nebula, planetary nebula), M2 (globular cluster), and NGC7293 (Helix Nebula).

By 0005 MST, the humidity was up to 46%. Began closing up for the night.

The observatory was closed at 0016 MST, 66°F.

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

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