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Mercury, Cat's Eye Nebula

Last updated: 1 July 2011

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Tuesday, 28 June 2011, dawned cloudy. Even after most of the clouds disappeared in the late afternoon, the sky was very hazy. No observing. Clouds from the beginning of the Monsoon weather pattern continued on Wednesday, 29 June. And the first storm of the Monsoon season arrived at midnight, with lightning, thunder, and some brief rain. Clearing began mid-morning. Opened the observatory Thursday, 30 June, at 1810 MST, 111°F. At 1820 MST, SYNCed and focused the 8" LX200-ACF on Spica and then viewed Mercury, low in the western sky. At 77X and 206X, there was a nice "half-moon" phase visible. I set up for iPhone 4 afocal imaging using the MX-1 adapter. Due to the low altitude poor seeing, the best image (cropped) was a single frame in a video recording, afocal 666X:


Next, I updated the ISS TLE for the night's pass. The data downloaded earlier in the day from Heavens-Above was two days old. I then resumed observing Mercury until it got too low. At 1920 MST, went to Saturn. At 1944 MST, Titan became visible at 133X. Rhea appeared at 1956 MST. At 2000 MST, Dione appeared, followed by Tethys. Iapetus made its appearance at 2007 MST. At 2023 MST, saw the first of two Kissing Bugs of the night. Terminated (as was the second one).

I began preparing for the ISS pass at 2050 MST. Did a focus test with the D7000 DSLR at prime focus + 3X TeleXtender using the star Vega and the Bahtinov Mask. Then I did a test video at 1/2000sec, ISO 1600. Vega was imaged. While waiting for the pass to start, I noticed this praying mantis on the observatory dome:


At 2120 MST, the ISS appeared, two minutes late. The TLE was too old. Tracking was so far off that I never managed to catch up with the ISS during the 5 minutes of video recording with the D7000. Too bad, as this was a nice high pass.

I then set up to image NGC6543, the Cat's Eye Nebula. Did a focus test on Deneb at prime focus. Slewed to the nebula and began imaging. Unfortunately, the focus slipped and none of the images were good. So, I went to Vega and redid the focus. I then did 30, 20, and 10 second, ISO 1600, exposures of NGC6543. The 30 second and 20 second images had the nebula overexposed. The best was this 10 second, unguided, cropped, image:


I ended DSLR imaging at 2209 MST. At 2225 MST, viewed M8 (Lagoon Nebula), M17 (Swan Nebula), and M20 (Trifid Nebula) in the 26mm eyepiece to determine which DSO might be best for tests with the iPhone 4. I selected M17. Added the focal reducer and set up to image M17 with the iPhone with the 26mm eyepiece. The tests failed; neither "Slow Shutter" nor "Slow Shutter Cam" were able to capture M17.

I left the focal reducer attached and using the 26mm eyepiece viewed M8, M16 (Eagle Nebula), M17, and M20. I then viewed NGC6960 (Veil Nebula). Added the O-III filter; the Veil really stood out. I then viewed NGC6888 (Crescent Nebula) with and without the O-III filter. It was visible with or without the filter, but the contrast was greater without the filter.

Closed the observatory at 2312 MST, 80°F.

Some other notes:

I have added a "Satellite Tracking" article on the Links page. It consolidates my notes onto one page. I will update the article as appropriate.

I have now completed the initial stage of redesigning this web site. If you find any broken links, please let me know. As part of the redesign, the Photos page now has more categories.

For those who might be interested, here is my DSO log file (Excel) showing most of the DSOs I have imaged and what exposure settings were used. The log has data for both the Nikon D70 DSLR and Nikon D7000 DSLR. Feel free to use it as a guide for your imaging.


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