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New Addition at Observatory;
Imaging: Venus, Comet 41P, More Galaxies

Posted: 25 March 2017

Cloudy skies returned on Wednesday, 22 March 2017. Thursday morning, 23 March, there was some rain (0.14") and a lot of small hail that turned the ground white. Strong winds came up mid-day. Clear skies returned on Friday, 24 March. The wife and I assembled and set up three benches on our land, including one at the observatory:


Open: Friday, 24 March 2017, 1807 MST
Temperature: 84°F
Session: 1090
Conditions: Clear

Equipment Used:
12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 9mm 100° eyepiece
1.25" 5.5mm eyepiece

iPhone 6s Plus
D7200 DSLR

1813 MST: LX600 ON, StarLock OFF, High Precision OFF.

1817 MST: viewed the thin crescent phase of the planet Venus, 102X, low in the western sky and through tree limbs. 1822 MST: Took this handheld iPhone 6s Plus photo, afocal 102X, using the iOS app NightCap Pro:


(The dark splotches are from the tree limbs.)

1825 MST: began setting up the iOptron SkyTracker Pro with the D7200 DSLR on the observatory patio for imaging Comet 41P/Tuttle-Giacobini-Kresak after the end of Astronomical Twilight:


I then checked out the new bench on the observatory patio, with and without a seat cushion. It was very comfortable and convenient. I could even recline on the bench, which will be handy for watching meteors showers.

1841 MST: sunset.

1842 MST: viewed the planet Mercury, 102X. Its gibbous phase was visible.

1907 MST: began trying to observe Sirius B (the "Pup Star") using 102X, 271X, and 443X. Sirius was at the central meridian, so was at its highest in the southen sky. With the sky still somewhat bright I hoped that the glare from Sirius A would be reduced. Unfortunately, I was not able to see Sirius B.

Next, I did some planning for the night's Deep Sky Object (DSO) imaging.

1935 MST: polar aligned the SkyTracker Pro. 1942 MST: I was now ready to begin imaging Comet 41P. The temperature had dropped significantly so took a short break to get into some warmer clothes. 1954 MST: returned to the observatory.

1956 MST: viewed Comet 41P using the Vortex 12x50 binoculars. The still faint comet was visible in the bowl of the Big Dipper, with a rather large coma seen in the binoculars.

2000 MST: began imaging Comet 41P/Tuttle-Giacobini-Kresak with the D7200 DSLR. This is a tracked f/3.5, 221 seconds, ISO 1600, White Balance 3570K, FL 18mm, image (slightly cropped):

Mouseover or tap on image
Mouseover or tap on image for label

A very faint satellite is visible crossing left-to-right near the star Mizar.

This is a tracked f/3.5, 5 minutes, ISO 2500, WB 3570K, FL 60mm, image (slightly cropped) showing the comet's coma in the bowl of the Big Dipper:


2039 MST: ended comet imaging.

Returned to the 12" telescope and viewed the galaxies M91 and M94, 102X. Then slewed to the star Denebola, mounted the DSLR at prime focus + focal reducer, focused using the Bahtinov Mask, and locked the primary mirror.

2100 MST: slewed to M94. StarLock ON. Began imaging some Messier galaxies for the update to my Messier Catalog Astrophotography Album. These are StarLock autoguided, 5 minutes, ISO 6400, WB 3570K, slightly cropped, images:





Slewed the 12" telescope to the colliding galaxies NGC4038/4039, still somewhat low in the southeastern sky. I decided to try imaging anyway although StarLock autoguiding was not very good due to the low altitude in the sky. This is a StarLock autoguided, 5 minutes, ISO 6400, WB 3570K, slightly cropped, image:

NGC4038 and NGC4039

The extended arms are faintly visible to the left and right of the galaxies. I will try for a better image on a future session.

2206 MST: StarLock OFF. Ended DSO imaging.

2217 MST: viewed NGC4038/4039, 102X. The view of the galaxies was pretty good using averted vision.

Then viewed the galaxies M98 and M99, 102X. Nice views.

2223 MST: LX600 OFF.

Close: Friday, 24 March 2017, 2233 MST
Temperature: 50°F
Session Length: 4h 16m
Conditions: Clear

If you are into old astronomy books like I am, check out "The Amateur's Telescope" by Wm. F.A. Ellison", published in 1920. Thanks to Armagh Observatory for making it available online.

And this is important for all of us: American Astronomical Society Council Issues New Resolution on Light Pollution.

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