OBSERVER’S CHALLENGE* – APRIL, 2022
by Glenn Chaple
NGC 3079 Barred Spiral Galaxy in Ursa Major (Magnitude 10.9; Size 7.9’ x 1.4’)
If you’re a fan of edge-on or nearly edge-on galaxies, you’ll love this month’s Observer’s Challenge- the barred spiral galaxy NGC 3079 in Ursa Major. Modern observations reveal a 3000 light year wide gaseous “bubble” emanating from the galaxy’s center, created either by a massive black hole or a burst of star formation.
By chance, I was in the neighborhood of NGC 3079 on the evening of April 28, 1976 when I viewed the double star Struve 1402 (magnitudes 8 and 9, separation 33”) with a 3-inch f/10 reflecting telescope. The pair was faintly seen, as was a 10th magnitude companion, 132” south of the main star. NGC 3079 was less than a half degree north-northwest of Struve 1402, but there is no way I would have glimpsed the 11th magnitude galaxy with this little scope.
On the evening of March 21, 2022, I sought out NGC 3079 with a 10-inch f/5 reflector. Plugging the galaxy’s 2000.0 coordinates (RA 10h 01m 57.8s, Dec. +55o 40’ 47”) into the AAVSO’s online Variable Star Plotter (VSP), I came up with a finder chart that showed a star-hop pathway connecting it to the nearby 4th magnitude star upsilon (υ) Ursae Majoris. Low power eyepiece in place, I followed a path 3 degrees south-southeast from upsilon to a triangle of 8th and 9th magnitude stars which lies just south of NGC 3079. Increasing the magnification to 141X, I spotted a faint, elongated smudge just northwest of the northernmost star in the triangle. The bright central region was barely visibly directly, while averted vision fleshed out the outer extensions, which ran roughly north to south.
NGC 3079 was discovered by William Herschel on April 1, 1790. A recent calculation indicates a distance of 54 million light years.
*The purpose of the Observer’s Challenge is to encourage the pursuit of visual observing. It is open to anyone who is interested. If you’d like to contribute notes, drawings, or photographs, we’d be happy to include them in our monthly summary. Submit your observing notes, sketches, and/or images to Roger Ivester (email@example.com). To find out more about the Observer’s Challenge, log on to rogerivester.com/category/observers-challenge-reports-complete.
NGC 3079 Finder Chart A
Chart created using AAVSO’s Variable Star Plotter (VSP). Numbers indicate stellar magnitudes, decimals omitted. Magnitude 3.8 star is upsilon (υ) Ursae Majoris. Stars plotted down to magnitude 10. North is up in this 3½ by 2½ degree field.
NGC 3079 image
Mario Motta MD (ATMoB) 32-inch f/6 scope with STL 1001E Camera, about 1 hour total integration. North is up. The faint galaxy at upper right is CGCG 265-55, magnitude 14.8.