Deep-Sky Companions: The Caldwell Objects
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The Caldwell Catalogue, compiled by the late Sir Patrick Moore (1923-2012), has delighted amateur astronomers worldwide since its publication in 1995. Twenty years on, Stephen James O'Meara revisits his guide to these 109 deep-sky delights, breathing new life into them and the 20 additional observing targets included as an appendix. This second edition retains O'Meara's detailed visual descriptions and sketches, accompanied by stunning new images taken by amateur photographer Mario Motta and observations by Magda Streicher. The astrophysical descriptions have been updated to account for the many advances in our understanding of the objects, not least due to an armada of space-borne observatories and the new technologies used in large ground-based telescopes. Ideal for observers who have completed the Messier objects and are looking for their next challenge, Deep-Sky Companions: The Caldwell Objects is a fitting tribute from a renowned visual observer to one of astronomy's most famous personalities.
The full name, so it became the Caldwell Catalog. Having completed my list, I put it in an envelope and sent it off to Sky & Telescope. To be candid, I thought very little more about it. Creating the list had been an interesting exercise, but would anyone else be interested in it? I was absolutely taken aback by the reaction. Sky & Telescope gave it full space in its December 1995 issue; other observers took it up, and before long I realized that the Caldwell VIII Catalog had really taken off.
It consists of only a few members. But no final determination has been made. The cluster is 76 million years young — similar in age to the Pleiades. Deep-Sky Companions: The Caldwell Objects 17 & 18 17 NGC 147 Type: Elliptical Galaxy (E5 pec) Con: Cassiopeia RA: 00h33.2m Dec: +48° 30' Mag: 9.5 Dim: 17.8' x 11.0' SB: 14.7 Dist: 2.3 million light-years Disc: John Herschel, 1829 J. H E R S C H E L : [Observed 8 September 1829] Very faint, very large, irregularly round, 4' to 5' diameter, GC/NGC:.
Observer was, in the words of French author Georges Simenon, "a little island in a great ocean of nonknowledge." Today we know that NGC 4449 is an active star-forming dwarf galaxy seen at a 43° angle from face on. It has a bar running through it, much like the one we see in the Large Magellanic Cloud. The galaxy is surrounded by an enigmatic halo of diffuse hydrogen gas some 10 times larger than the galaxy's visible disk. At its estimated distance of 10 million light-years NGC 4449 has a modest.
Evening, not so long ago, while I was out browsing around the sky. I looked casually at NGC 7293, the Helix Nebula in Aquarius, and wondered why it did not have a Messier number; it could easily be taken for a large comet. And there are many other objects of equal or greater interest than those with "M" designations. Many of these non-Messier sights are shamefully neglected. I am not a reputed deep-sky observer. My subject is the Moon, and I like to joke that anything beyond the orbit of Neptune.
12' southeast of that star and 8' northeast of a wide pair of 9.5magnitude stars. If your telescope offers a 2° field of view, the star-hopping described here will be a cinch. A 3° field of view can take in a nice triangle made up of Gamma Pegasi, the magnitude-6.6 star north of it, and the galaxy. NGC 7814 is an almost exactly edge-on spiral that belongs to the Pegasus Spur of galaxies, which includes NGC 7331 (Caldwell 30). Its recession velocity is 1,047 km per second. If its estimated.