Object: Constellation: Coordinates: Size: Brightness:
NGC 3184 UMa 10h18m / +4125' 7.4' x 6.9' 9.6mag

The spiral galaxy NGC 3184 in the constellation Ursa Major on March 23 / 24 and April 14 / 15, 2015. The galaxy is approximately 40 million light years from Earth and was discovered by William Herschel in 1787 (source: Wikipedia).

Thirty-two 3 minute exposures at ISO 800 with no dark frame subtraction were stacked with Deep Sky Stacker (resulting in a 1 h 42 min exposure) and further processed in Photoshop.
Equipment: Canon EOS 450D Baader modified camera, TeleVue Paracorr Type II coma corrector, 16" f/4.5 "Ninja" dobsonian telescope riding on a dual-axis Tom Osypowski equatorial platform, Lacerta MGEN autoguider, Lacerta off axis system (field of view comparison: image of the moon with the same equipment).

Search chart for NGC 3184. Map © 2015 "The Mag-7 Star Atlas Project", www.siaris.net. Map is modified. The map can be downloaded here .