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Comet PanSTARRS, Dwarf Galaxy Leo I,
Dwarf Planet Makemake

Posted: 14 March 2013

A replacement for the clip-on 6" fan that failed in October 2012 after 2.5 years of use was received on 28 December 2012. I decided to wait for hotter outside temperatures before installing it in the observatory. It was installed on 13 March 2013.

Opened the observatory Wednesday, 13 March 2013, at 1808 MST, 84°F. After last night's nice Comet PanSTARRS and crescent moon photo op, I decided I would image Comet C/2011 L4 (PanSTARRS) through the 8" LX200-ACF. As I was opening the door to the observatory, this little birdie decided to check on what I was doing:


I attached the focal reducer to the 8" LX200-ACF. At 1824 MST, I picked up the thin crescent moon with the naked eye. The sky was still bright as the sun about 6 minutes from setting. At 1828 MST, viewed the moon through the telescope. I then mounted the D7000 DSLR at prime focus + focal reducer, and captured this image of the moon at 1831 MST, 1/250sec, ISO 400:


I connected the iPhone 4 to the telescope using the SkyWire cable and used SkySafari Pro to slew the telescope to Comet C/2011 L4 (PanSTARRS). At 1847 MST, the comet became visible in the camera viewfinder. I then began imaging the comet every few minutes. At 1859 MST, the comet became visible in the 8x50 finderscope and 7x50 binoculars. The sky was still bright but a short tail was visible. At 1903 MST, the comet became faintly visible to the naked eye. At 1920 MST, I used the iPhone to capture this "live view" of the comet as seen by the D7000 DSLR through the 8" telescope:


This telescopic view of the comet was captured at 1924 MST at prime focus + focal reducer, 4 seconds, ISO 2000:


I continued to monitor the comet as it became lower in the sky, eventually getting into the trees as viewed from the observatory. I removed the camera from the telescope and viewed the comet with the 26mm eyepiece until 1938 MST. The comet showed a good nucleus, coma, and short tail.

I removed the focal reducer and began some brief lunar observing, 77X, at 1940 MST, followed by Jupiter and the four Galilean Moons.

At 1959 MST, viewed the Leo Galaxy Triplet (M65, M66, and NGC3628), all in the same field-of-view (FOV) at 77X. Then viewed the galaxies (also in the constellation of Leo) M105, NGC3384, and NGC3389. My previous images (a year ago) of these galaxies were all taken with 2 minute exposures; I wanted to try for longer exposures this night. At 2011 MST, did a focus test image on the star Regulus using the Bahtinov Mask. I then slewed to M105 and began searching for a guide star and doing framing test exposures. I eventually located a very faint guide. Unfortunately, it was too faint and I kept losing sight of it. This was the best guided exposure, 5 minutes, ISO 6400:


I will try again on the next session. Hopefully I will locate a better guide star.

I then slewed to the dwarf galaxy Leo I. This large but very faint galaxy is only 20' from the bright star Regulus so I wondered if I would be able to capture it. I used SkySafari on the iPhone to GOTO the galaxy. I was able to use Regulus as a guide star for this 10 minute, ISO 6400, slightly cropped, image:


I then tried to image the Leo Triplet (M65, M66, NGC3628). However, I was not able to get all three in the same camera FOV at prime focus. I would need to use the focal reducer, so I deferred imaging the Triplet until the next session.

I then used SkySafari to slew the telescope to the dwarf planet Makemake. I had previously taken an image of Makemake on 1 March 2013, but clouds and travel prevented acquiring a confirming image showing movement. After initially slewing to Makemake I tried to find a guide star, but could not find a good one. I re-oriented the camera, redid the focus test on Regulus with the Mask, and slewed back to Makemake. I eventually located a faint guide star, but I had to slew a long ways to get it centered in the illuminated reticle eyepiece and I wasn't certain that the faint Makemake (Magnitude +16.9) would still be in the camera FOV. I decided to try anyway. During post-processing I used SkySafari on the Mac to identify stars in the image FOV and located what I believe is the dwarf planet Makemake:


I plan to acquire a confirming image on the next session in the observatory. I ended imaging this night at 2154 MST. I briefly viewed the galaxy NGC4244, 77X, and then began closing the observatory.

Closed the observatory at 2218 MST, 63°F.

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

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