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Submitted: Fri, 2017-10-27 09:32

M 71

Messier 71 (also known as M71 or NGC 6838) is a globular cluster in the constellation Sagitta. It was discovered by Philippe Loys de Chéseaux in 1745 and included by Charles Messier in his catalog of comet-like objects in 1780. It was also noted by Koehler at Dresden around 1775.

The star cluster is at a distance of about 12,000 light years away from Earth and spans some 27 light years across. The irregular variable star Z Sagittae is a member of this cluster.

R = 11 * 500 sec. bin1, G = 11 * 600 sec. bin1, B = 11 * 700 sec. bin1.

PixInsight 1.8, Photoshop CC

M 71
Submitted: Sun, 2017-10-08 16:26

Abell 2218

Abell 2218 is a cluster of galaxies about 2 billion light-years away in the constellation Draco.

Acting as a powerful lens, it magnifies and distorts all galaxies lying behind the cluster core into long arcs. The lensed galaxies are all stretched along the cluster's center and some of them are multiply imaged. Those multiple images usually appear as a pair of images with a third — generally fainter — counter image, as is the case for the very distant object. The lensed galaxies are particularly numerous, as we are looking in between two mass clumps, in a saddle region where the magnification is quite large.

L = 31 * 1800 sec. bin1, RGB = 9 * 1800 sec. bin1.

Total exposition - 29 hours.

Pixinsight 1.8 and Photoshop.

Abell 2218
Submitted: Sun, 2017-10-01 14:54

NGC 7662

NGC 7662, also known as the Blue Snowball Nebula or Snowball Nebula, is a planetary nebula located in the constellation Andromeda.

The distance to this nebula is not known with any real accuracy. According to the Skalnate Pleso Catalogue (1951) the distance of NGC 7662 is about 1,800 light years, the actual diameter about 20,000 AU. In a more recent survey of the brighter planetaries, C.R.O'Dell (1963) derived a distance of 1,740 parsecs or about 5,600 light years, increasing the actual size to 0.8 light year, or nearly 50,000 AU. It has a faint central star that is variable, with a magnitude range of 12 to 16. The central star is a bluish dwarf with a continuous spectrum and a computed temperature of about 75,000K. The nuclei of the planetary nebulae are among the hottest stars known.

Ha = 20 * 1800 sec. bin1, OIII = 10 * 1800 sec. bin1, OIII = 20 * 900 sec. bin1.

Total exposition is 20 hours.

Pixinsight 1.8 and Photoshop.

NGC 7662