Globular Cluster M53 (NGC 5024), class V, in Coma Berenices

RA 13:12.9; DEC +18:10; Distance 59.700 light years;
Visual Brightness: 7.6; magnitude; Apparent Dimension 12.6 arc minutes.

In small amateur telescopes, M53 appears as a slightly oval nebulous object with a large, bright center, of rather even surface brightness and evenly fading out to the edges. Mallas reports that he saw many stars in the 4-inch refractor under excellent viewing conditions, with the central part appearing somewhat grainy. In somewhat larger telescopes, its outer fringes appear resolved into stars, while the central part is still unresolved and grainy, with one star standing out, in telescopes of about 8-inch aperture. Large instruments of about 12-inch up show it well resolved, with a moderately concenterated nucleus and stars spread out to about 12 arc minutes diameter.

Source and more: SEDS


April 22, 2009 20:17 - 20:53 UT & April 23, 2009 20:27 - 22:00 UT.
Imaging: William Optics Zenithstar 80 ED II APO, f/6.8 [focal length 545 mm], Astronomik Lum Filter; ATK16IC camera.
April 22, 2009: Exposures: Lum 5x240s + 1x420s [1x1]; RGB not captured; all unguided.
April 23, 2009: Exposures: Lum 9x360s [1x1]; RGB 5x90s; all unguided.

April 22, 2009 20:17 - 20:53 UT.
Imaging: William Optics Zenithstar 80 ED II APO, f/6.8 [focal length 545 mm], Astronomik Lum Filter; ATK16IC camera.
Exposures: Lum 5x240s + 1x420s [1x1]; RGB not captured; all unguided.

April 5, 2006 23:03 - 23:14 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.
26 autoguided exposures of 25 seconds.

April 22, 2003 22:25 UT; TAL-2M; Prime Focus; 6 x 45 seconds exposure.

April 1, 2003 00:15 - 00:27 UT; TAL-2M; Focal Reducer; 4 x 30 seconds exposure.