Galaxy Group NGC 3718, NGC 3729 and HG 56A

clic for 30% size 1187 x 828 (250 kB)

clic here for 50% size 1863 x 1283 (572 kB)


About this Image

Lying at a distance of about 52 million light years from earth, NGC 3718 (above center, also designated as ARP 214) is one of the most interesting and beautiful galaxies in the northern skies, it is situated in Ursa Major. It's unique warped shape, color and contrasting spiral dust lane make it one of my favorite objects, find literature about it here: 1

Classified as a barred spiral of the peculiar type with a Seyfert or LINER type nucleus, this galaxy most likely supports a massive black hole at its center. NGC 3718 is interacting with its cloes barred spiral companion NGC 3729 (below center).

The obvious Hickson Group 56A (Arp 322) at the top right corner of the image is located in approximately 425 million light years distance and consists of five main galaxies, identified as follows: PGC 35609, PGC 35615, the interacting pair PGC 35618 and UGC 6527, MGC 9-19-113. Numerous background galaxies beyond mag 20 are all around.

North is left.

Below you see a crop on NGC 3718 and the Hickson 56A group in 35/70% size.

The faint extensions of this galaxy can be seen better in the enhanced inverted greyscale view below in 35% size.

Even below you see a crop on the distorted barred NGC 3729 in 50% size.

clic for 70% size 1325 x 766 (276 kB)


Technical Details


16" cassegrain in secondary focus at f/10

Mount MK-100 GEM
Camera SBIG STL-11000M at -15C, internal filter wheel
Filters Astronomik LRGB
Date May 27-28, 2005, additional LRGB data added 2007.
Location Wildon/Austria
Sky Conditions mag 5.5 sky, L: raw FWHM 2.2-2.8", temperature 10-20 C
Exposure L:R:G:B = 150:30:30:30 minutes (10-minute sub-exposures), color binned 2x2;
2007: L:R:G:B = 200:80:60:80 minutes (20-minute sub-exposures)
Processing Image aquisition and calibration in Maxim, DDP and mild deconvolution in ImagesPlus; color balance, curves, unsharp mask, crop in Photoshop; Noise reduction by Neatimage;