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Venus, Lunar Crater Janssen,
Comet C/2013 R1 (Lovejoy) in Evening Sky

Posted: 8 December 2013

The observatory was opened Saturday, 7 December 2013, at 1648 MST, 54°F. Saw Venus naked-eye just prior to opening the observatory, 32 minutes prior to sunset. The sky was mostly clear, with strong breezes blowing almost continuously. There were some clouds low along the western horizon.

At 1655 MST, viewed Venus in the 8" telescope, 83X. I then began preparing for eyepiece projection imaging using the D7000 DSLR with a 1.25" 9mm eyepiece + 2" 2X PowerMate (yielding 444X). Seeing was lousy, probably from the wind, causing a lot of atmospheric distortion. I did several HD video recordings at various exposure settings. Sunset occurred at 1719 MST. This is one frame, slightly cropped, from a recording made at 1733 MST, 1/640sec, ISO 5000:


I then slewed to the moon, looked around for a nice high magnification target, and decided to image Crater Janssen, 444X. Seeing was not good enough for that much magnification. Removed the PowerMate and imaged at 222X. This is a single image, made using the "Hat Trick" Method, ISO 500:


I removed the camera from the telescope and did some lunar observing beginning at 1752 MST, 83X. Earthshine was visible. Seeing continued to be bad due to the strong breezes.

At 1808 MST, I put the telescope to sleep. I left the observatory and went to the front patio of the house, which has an obstructed view of the western sky. Clouds were still low along the western horizon. At 1817 MST, I spotted Comet C/2013 R1 (Lovejoy) using the Celestron Cometron 12x70 binoculars (handheld). It appeared as a faint fuzzy patch, with no tail visible, against a still bright sky. Over the next 30 minutes I took several photographs using the tripod mounted D7000 DSLR. This photo, taken at 1834 MST, f/5.6, 8 seconds, ISO 3200, 105mm focal length, shows Comet Lovejoy at the center:

(mouseover or tap to see labels and magnified inset)

A very slight tail is just barely visible in the slightly trailed image. See the inset for a better look. (Clouds are visible in the image. The orange glow at the bottom is due to the lights from Casa Grande city, south of Phoenix.)

I took a last look at Comet Lovejoy with the 12x70 binoculars at 1847 MST. It was just barely visible now. I never saw it using the naked eye due to the sky brightness.

I returned to the observatory and woke the telescope. The clouds had now reached Venus. I began closing up.

The observatory was closed at 1900 MST, 38°F.

For some nice photos of Comet Lovejoy in the morning sky as seen from Tucson, Arizona, check out The Half-Astrophysicist Blog by Rob Sparks.

Comments are welcome using Email. Thanks.

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