Instrument

12.5" RCOS @  ~f/9 (2880 mm fl) 0.643 arcsec / pixel.  Shown resampled to 2.57 arcsec / pixel.

Mount

Paramount ME

Camera

SBIG STL-11000 w/ internal filter wheel, AstroDon Filters

Acquisition Data

4/20/2009 to 4/27/2009  Chino Valley, AZ

Exposure

Lum    375 min (25 x 15 min, bin 1x1)

RGB    315 min ( 7 x 15 min each, bin 1x1)

Software

CCDSoft, CCDStack, Photoshop CS w/ the Fits Liberator plugin, Noel Carboni's actions and Russ Croman's Gradient Exterminator

CCDStack to register, normalize, data reject, combine and luminance sharpen.

PhotoShop for the color combine.

Comment

North is to the top.

At a distance of 30 million light years, NGC 3628 is a relatively close galaxy in the constellation Leo. NGC 3628, along with nearby M65 and M66 form the Leo Triplet galaxy group.

To the left, extending out of the frame, about one fourth of the galaxy's tidal tail is faintly visible. The tail extends for about 300,000 light years and is caused by interactions with the two large nearby galaxies. The tail is composed of young blue star clusters and star forming.

The second image shows the position of asteroid 35856 1999 JG64 on two successive nights. It first shows up in the blue exposures and then the next night in the red. It is not shown as neat blue and red straight lines because the CCDStack data rejection routines removed some of the data. More aggressive use of these routines would have completely removed the asteroid.