Cassiopeia Observatory

Venus, Milky Way, NGC4236 Galaxy, M16 Eagle Nebula,
Hercules Galaxies, DSO Observing, M74 Supernova SN2013ej
Posted: 30 July 2013

The monsoon weather pattern is taking a short break, so I was able to open the observatory again on Monday, 29 July 2013, at 1810 MST, 106°F. There were a few clouds low in the west and southwest. After opening the observatory I removed some spider webs that had been built up during my long absence from the observatory due to cloudy nights.

At 1828 MST, I began observing Venus at 83X and 222X. Its gibbous phase was clearly visible. I handheld the iPhone 4 over the 9mm eyepiece and did an afocal video recording. This is a crop from one frame of the video:

By 1920 MST, thin clouds were getting higher in the southern sky. Sunset occurred at 1927 MST. I continued to monitor the clouds as I waited for astronomical twilight to end (at 2059 MST). At 1933 MST, the clouds were in most of the southern half of the sky, but seemed to be mostly gone by 2000 MST. At 2017 MST, viewed Saturn, 83X and 222X. At 222X, not only was the Cassini Division distinctly and crisply visible, during brief moments of excellent seeing I could just make out the Encke Gap. First time I've seen it.

At 2045 MST, I began setting up to photograph the Milky Way using the D7000 DSLR with an 8mm fisheye lens (180°). I took many exposures beginning at 2054 MST. There were some clouds in Sagittarius and Scorpius that I had to contend with. At 2111 MST, I captured this (cropped) image, f/5, 30sec, ISO 5000:

Weather permitting, I will try for another image, sans local clouds, on the next session.

At 2122 MST, I began setting up to image NGC4236 (galaxy) at prime focus of the 8" LX200-ACF. It was low in the northwestern sky. I had planned to image it when it had been higher in the sky a few weeks ago but the continuous cloudy nights kept me from it. I did a focus test on Arcturus using the Bahtinov Mask. I then did two framing test exposures of NGC4236 while looking for a suitable guidestar. I then took this (cropped) guided, 5 minute, ISO 6400 exposure:

I will re-do the image when NGC4236 is better positioned several months from now.

Next, I slewed to M16 (Eagle Nebula), and located an excellent guidestar. Did a framing test exposure and then captured this 10 minute, ISO 6400, guided (cropped) image:

At 2212 MST, the sky was mostly clear once again. I slewed to NGC6050/IC1179 (colliding galaxies) in Hercules and did a 1 minute, ISO 6400, framing test exposure after locating a suitable guidestar. The galaxies were too faint to be visible on the camera screen so I decided to do the exposure. This is a full-frame, guided, 10 minute, ISO 6400 exposure:

The faint colliding galaxies NGC6050 and IC1179 are below the center of the image, with many other galaxies in Hercules visible over the entire image.

I ended imaging at 2238 MST. Viewed M13 and M92 globular clusters in Hercules, 83X. I then did a tour of DSOs in Sagittarius: open clusters M23, M21, NGC6530, M24, M25; globular clusters M28, M69, M22, M70, M54, M55, M75; nebulae M20 (Trifid), M8 (Lagoon), M17 (Swan); and Barnard's Galaxy NGC6822. I then returned to M16 for some viewing of it, 83X.

At 2310 MST, viewed M31 (Andromeda Galaxy) and its companion galaxies M32 and M110, 83X. At 2322 MST, I noticed that some clouds had appeared in the southern sky again. Beginning at 2330 MST, I did a tour of DSOs in Cassiopeia, 83X: open clusters NGC129, NGC225, NGC457, NGC559, M103, NGC654, NGC659, NGC663, M52, NGC7789; galaxies NGC147, NGC185; and the Bubble Nebula NGC7635 (barely visible).

At 2359 MST, M74 (galaxy) had just risen above the hill to the east. The new supernova 2013ej might have been just detectable at 83X but the galaxy was too low in the sky to be certain. The eastern sky was beginning to brighten due to the rising waning moon. I began setting up to image M74 and the supernova at prime focus. The sky continued to get brighter and a thin cloud band soon arrived at the position of M74. At 0019 MST, the clouds had moved mostly away from M74 and I captured this guided, 5 minute, ISO 6400, (slightly cropped) image:

I ended imaging due to the rising moon and clouds. I tried to see the supernova in M74 at 83X but clouds and moonlight made it invisible.

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