Spiral Galaxy M109 (NGC 3992), type SBc, in Ursa Major

RA 11:57.6 (h:m) DEC +53:23 (deg:m); Distance 55 million light years
Visual Brightness 9.8 (mag); Apparent Dimension 7x4 (arc min)

M109 is one of the "Theta"-like barred spirals, which appears as a "hazy spot" situated just 40' SE of the mag 2.44 star Gamma Ursae Majoris (Phad, or Phecda).

This object was observed by Pierre Méchain on March 12, 1781, and by Charles Messier on March 24, 1781, together with M108 when he measured M97. Messier listed the object now called "M109" under number "99" in a preliminary manuscript version of his catalog without a position, and Méchain mentioned it in his letter to Bernoulli of May 6, 1783. But together with M108, it was not added to the "official" Messier catalog until 1953, by Owen Gingerich. William Herschel has found this galaxy independently on April 12, 1789, and cataloged it as H IV.61 (incorrectly misclassifying it as a planetary nebula).

M109 is about 7-by-4 arc minutes in angular extent, and of apparent visual magnitude 9.5 or 9.6. Visually, only its bright central region together with the bar can be seen, and appear pear-shaped in smaller telescopes, "with a strong suspicion of a granular texture" (Mallas).

Source and more: SEDS


March 20, 2006 22:14 - 22:34 UT.
Imaged with LX200 10-inch f/10 telescope with 0.33 Focal Reducer operating at f/4.06 [focal length 1015mm], Vesta Pro-SC3a b/w RAW mode, Baader Infra Red Blocking Filter.
40 autoguided exposures of 20 seconds.


April 24, 2004 22:01 - 22:13 UT.
Note: UGC6969 Galaxy, magnitude 15.2 is just visible [rather high at the left border of the image].









Same image as above, but now preprocessed with Jon Grove's iPrep (thank you Jon !)