Fisheye Lens Sky, M82 Galaxy Supernova SN2014j,
Posted: 23 January 2014
Opened: Wednesday, 22 January 2014, 1812 MST
Conditions: Partly cloudy, occasional breezes
After several cloudy nights in a row, it was good to head back out to the observatory. The forecasts for the night had partly cloudy skies, but I wanted to try to view and image the newly discovered supernova SN2014j in the M82 galaxy. It was reportedly about Magnitude +11. On the way to the observatory, I took this photograph of the western sky showing come crepuscular rays after sunset, D7000 DSLR, f/3.5, 1/20sec, ISO 400, 8mm fisheye lens:
At 1820 MST, viewed Jupiter, 83X and 222X. The four Galilean Moons were visible, but thin clouds hampered the view. I would not try any video recording tests this night.
At 1830 MST, slewed to the M82 galaxy. It was not yet visible using 83X due to the still bright sky. Astronomical Twilight would not end for another 43 minutes. I then began setting up for fisheye sky photography. After mounting the D7000 DSLR on a photographic tripod outside of the observatory, I returned to the 8" LX200-ACF, and at 1838 MST, the M82 galaxy and the supernova were easily seen at 83X against a still somewhat bright sky.
I began taking sky photos at 1903 MST and completed the photography at 1927 MST. I had to delay some photos due to passing aircraft. This photo was taken at 1918 MST, f/5, 30 seconds, ISO 1600, 8mm fisheye lens:
Orion is at the upper right, the star Sirius just above the hill on the right, and Jupiter in Gemini near the above center. The Winter Milky Way is visible left of Orion down to Sirius.
Viewed Jupiter again at 1929 MST, 83X and 222X. The view was surprisingly good. Apparently, the clouds had gone away.
Slewed to M82 at 1933 MST and viewed it at 83X and 222X. The supernova was very obvious. No averted vision was required to see it. I then began preparing for 8" prime focus imaging with the D7000 DSLR using the off-axis guider. After doing a focus test on the star Pollux using the Bahtinov Mask, slewed to M82 and did some framing test exposures while searching for a good guide star. Located a guide star with good framing. This is a full-frame, unguided, 1 minute, ISO 6400, exposure showing the bright supernova SN2014j:
This is a guided, 5 minute, ISO 6400, exposure, rotated and cropped:
This is a stack of 5 images, 2 minute exposures, ISO 6400, for an effective exposure of 10 minutes, and cropped:
Mouseover or tap the image to see the supernova arrowed
I completed M82 imaging at 2030 MST. There were some clouds in the northwestern sky. I then tweeted this iPhone 5s photo of M82 as seen on the D7000 DSLR screen (1 minute, ISO 6400, exposure):
For comparison, here is a pre-supernova image of M82 I took on 28 January 2011, animated with an image showing SN2014j:
I began setting up to image NGC4236 galaxy. It was still low in the northern sky. Added the focal reducer to the 8" telescope since the galaxy is rather large. Slewed to Pollux, which would be the focus test star, at 2053 MST. Then began waiting for NGC4236 to rise higher in the sky while monitoring the sky conditions. At 2153 MST, the Winter Milky Way was nicely visible running from the northwest through the zenith down to the southeast. At 2115 MST, did the focus test on Pollux with the Bahtinov Mask. I decided I had better try to image NGC4236 while the sky conditions were good even though the galaxy was still low in the sky. Did some framing test exposures while searching for a good guide star. Got a good star but with lousy framing. Decided to try it. This is a cropped, prime focus + focal reducer, 5 minute, ISO 6400, guided exposure, cropped, taken at 2133 MST:
After I completed the above image, I noticed that the sky seemed "fuzzier" now due to clouds. Part of the handle of the Big Dipper was obscured by cloud. At 2155 MST, clouds were now obvious in the southeastern sky as well. I decided to not do anymore imaging this night. I will try to get a better image of NGC4236 on another session.
At 2208 MST, took a last look at the M82 supernova, 83X. Then viewed Jupiter, 83X. Only three moons were now visible. Switched to 222X. The Great Red Spot was visible, just rotating into view. And a moon's shadow had just started its transit across the planet's disk. The transiting moon was not visible however.
Closed: Wednesday, 22 January 2014, 2224 MST
Comments are welcome using Email. Thanks.
Cassiopeia Observatory Home Page