Polar treats

just a few worth finding ,

NGC 40 – Bow Tie Nebula

The planetary nebula NGC 40, sometimes referred to as the “Bow tie” nebula, is located in Cepheus.
NGC 40 was discovered by William Herschel on November 25th, 1788. It is a spectacular object! This planetary is a bright (magnitude 10.7), slightly oval-shaped disk, 48″ across, with a conspicuous magnitude 11.5 central star. Brighter areas along the eastern and western edges mimic the appearance of the polar caps of Mars. The western “cap” seems to run off the disk. The “polar cap” effect is only visible on the best of nights.
NGC 40 is composed of hot gas around a dying star. The central star has ejected its outer layer which has left behind a hot, white dwarf core with a surface temperature about 50,000 degrees Celsius; radiation from this star heats the outer layers to about 10,000 degrees.
NGC 40 is about 3,500 light years away, and about one light-year across. About 30,000 years from now, NGC 40 will fade away, leaving only a white dwarf star approximately the size of Earth. This appeared bright , even in a TAL 100.

 

NGC 188, “The Ancient One” in Cepheus.

Ninth magnitude NGC 188 is one of the oldest known open clusters. Its estimated age, 9 billion years, is about that of the youngest globular clusters. NGC 188’s brightest stars, 12th to 13th magnitude objects, are yellow class III giants with spectra of G8 to K4. The cluster completely lacks white main sequence stars.

NGC 188 was discovered by John Herschel on November 3, 1831 and cataloged as h 34 in his 1833 catalog. This object subsequently became GC 92 in his 1864 General Catalogue, and finally NGC 188 in Dreyer’s NGC.
This cluster is within 5 degrees of the north celestial pole. It is moderately faint, with a combined magnitude of 8.1. Three dozen pinpoint stars resolve in a rich, concentrated background glow spanning a 14′ area. NGC 188 is a nice but faint, round cluster of fifty to sixty 12th to 15th magnitude stars twinkling in and out of resolution against a granular background. Several dark gaps lie west of the cluster’s center. Several wide star-pairs stand out.
Unlike most open clusters that drift apart after a few million years because of the gravitational interaction of our galaxy, NGC 188 lies far above the plane of the galaxy. NGC 188 is at an estimated distance of 5,000 light year, putting it slightly above the Milky Way’s disc, and further from the center of the galaxy than the Sun.
NGC 1888 is over 5 billion years, and is one of the most ancient open clusters known in our Galaxy. It consists of about 120 stars; the hottest main sequence star is of spectral type F2 V, while the 10 brightest stars are yellow giants of spectral types G8 III to K4 III. These have apparent magnitudes of about 12 to 14, corresponding to absolute magnitudes of +0 to +2. I’m very much drawn to the obscure and unique targets , such as NGC2419 and the Methuselah Star in Libra, this joins those ranks.

Dont forget , the bright “Cat’s Eye” nebula in Draco, NGC 6543,

Nick.

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