Observer’s Challenge Link:  APRIL 2016 OBSERVERS CHALLENGE – NGC-3077

The following pencil sketch was made using a 10-inch reflector, and a  5 x 8 blank notecard with the colors inverted via scanner.  Roger Ivester

NGC 3077 – Galaxy – Ursa Major
Date: April 25, 2016
NELM: 5.0
Telescope: 10-inch Newtonian reflector
Eyepiece: 12.5 mm + 2.8x Barlow
Magnification: 256x

At 57x, fairly easy to see, appearing mostly as a circular glow. At 91x, the galaxy becomes elongated with a NE-SW orientation, and a brighter central region, however, subtle. When increasing the magnification to 256x, a stellar nucleus is visible, but cannot be held constantly. The surface brightness of this galaxy is fairly low, making it difficult from my moderately light polluted backyard.

After viewing close neighboring galaxies, M81 and M82, which are much brighter and larger, NGC 3077 can be difficult, and maybe even a bit disappointing.

Roger Ivester

The following report and images are courtesy of Dr. James Dire of Hawaii.

NGC 3077
By Dr. James R. Dire

NGC3077 is a peculiar galaxy located in Ursa Major near the galaxy pair M81 and M82. The galaxy was discovered by William Herschel on November 8, 1801. Although the galaxy looks like an elliptical galaxy in the eyepiece, images of it show it has wispy edges and dark dust lanes, atypical of elliptical galaxies. Carl Seyfert included it in his list of active galaxies (now called Seyfert galaxies) in 1943. Today it is considered an irregular galaxy. Its distorted shape is probably casued by gravitational interactions with the large spiral galaxy M81, similar to Barnard’s Galaxy, NGC6822, which is equally close to the Milky Way.

Magnitude estimates for NGC3077 range from 9.9 to 10.8. The galaxy is 5.3′ x 4.4′ in size and is located 12.8 ± 0.7 Mly away. The galaxy is located three-quarters of a degree east-southeast of M81.

The first image was taken with a Stellarvue SV102 102 mm apochromatic refractor at f/6.3 using a Televue 0.8x FF/FR. The camera was a Canon 30D and the exposure was 60 minutes. In all images, north is up and east to the left. Image 1 was framed to have M81 and M82 centered. NGC3077 is labeled in the lower left-hand corner of the frame.

The second image was taken with a 10″ f/6 Newtonian with a Paracorr II coma corrector, yielding an f/6.9 optical system. A SBIG ST-2000XCM CCD camera was used. The exposure was 100 minutes. I really need 300-400 minutes of data to bring out the wispy edges and dark dust areas of the galaxy. But they can (barely) be seen in this short exposure. Unfortunately, time and weather did not allow more imaging before submitting this report.

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