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Observatory Update, Total Lunar Eclipse Washout,
Comet C/2013 A1 Siding Spring

Posted: 11 October 2014

Overcast skies returned on Monday, 6 October 2014, as another Pacific storm (Simon) began affecting the weather at Cassiopeia Observatory. That afternoon I had an excellent meeting at the observatory with the metal shop people who will be fabricating my telescope pier (using blueprints from SkyShed; thanks Wayne!). Cloudy skies continued and prevented viewing of the total lunar eclipse during the early morning hours of Wednesday, 8 October. Rain began just as totality began. So this eclipse was a washout. By the end of the day the rain total was about 0.8".

But in the GREAT NEWS category, I was notified on Wednesday, 8 October, that the International Dark-Sky Association Board of Directors has approved the designation of Oracle State Park as an “International Dark Sky Park”. It is the first Park in the Arizona State Parks system to receive this important designation. Press Releases will be coming out soon and a BIG celebratory event is being planned by my Committee and Arizona State Parks.

In other news, the replacement shortwave receiver for the observatory, a Grundig S450DLX Deluxe AM/FM/Shortwave Radio, was received on 8 October. Due to rain on Wednesday and Thursday, I wasn't able to install the radio in the observatory. Storm total rain for the two days was over 1".

The sky began clearing Thursday night, 9 October, but I didn't open the observatory due to a meeting of the Oracle Dark Skies Committee.

I did go out to the observatory Friday morning, 10 October. The humidity was very high and apparently had been for the past couple of days (from the rain). Moisture had collected on many metal surfaces, even inside drawers. I have never seen that before in the over five years of having the observatory! I hoped everything would dry off by the evening since I planned to do some observing. I was able to set up the shortwave radio in the observatory:


It worked well to receive WWV time signals inside the observatory at 15 MHz during the daytime. I did not even need to attach an external antenna. Would test it at night using 5 MHz. May also have to add some red transparent tape over the LCD since it comes on automatically when any key on the radio is pressed.

Opened: Friday, 10 October 2014, 1810 MST
Temperature: 78°F
Session: 727
Conditions: Mostly clear, some clouds in NW, humid

1817 MST: checked the new shortwave radio. It received WWV at 5, 10, and 15 MHz, all with strong signals. SYNCed the observatory clock to WWV.

1819 MST: viewed Mars, 83X, in the southwestern sky. Small with no details visible. Then slewed to M6 (Butterfly Cluster, open cluster). Comet C/2013 A1 Siding Spring had been near the cluster on the previous night. A few stars were visible in the cluster at 83X about 20 minutes after sunset.

1828 MST: viewed Saturn, 83X, very low in the southwest. The moon Titan was visible. Then slewed back to M6.

1830 MST: did some software beta testing. Ended testing at 1900 MST.

M6 cluster was a nice view now at 83X. Used SkySafari Pro 4.2 and the GC Wi-Fi Adapter to GOTO Comet Siding Spring. Wasn't visible in the eyepiece. Slewed to the star Antares, mounted the D7000 DSLR at prime focus of the 8" LX200-ACF, and began to do a focus test image. As I focused on Antares it drifted behind a tree. Slewed to Alpha Sagittarius and used it as the focus star with the Bahtinov Mask.

1912 MST: did a 30 second, ISO 2500, unguided exposure of Comet C/2013 A1 Siding Spring. Did a 2nd exposure 5 minutes later. The comet was easily seen on both images using the camera's LCD screen. This is the result:

Mouseover or tap on image
Mouseover image or tap on it to see animated version

In between the two comet exposures I checked the radio LCD illumination to see if it was too bright for use in the observatory. It was not. The light comes on when the radio is turned on or a button is touched. It then goes off very quickly. I'll confirm that the LCD light is OK for night use over several sessions. If it does become a problem I'll use red transparent tape to cover the LCD.

1926 MST: after removing the camera from the telescope I attempted to see the comet at 83X. It was visible as a small, faint, fuzzy blob, with no tail visible.

1930 MST: did some sky quality measurements using a SQM-L meter and the iOS app "Dark Sky Meter". The readings were impacted by the high humidity. Then began closing up for the night due to the high humidity. The eastern sky was just beginning to brighten from the rising waning gibbous moon.

Closed: Friday, 10 October 2014, 1947 MST
Temperature: 65°F

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