NGC 188
Appearance
NGC188 | |
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![]() NGC 188 | |
Observation data (J2000epoch) | |
Right ascension | 00h48m26s[1] |
Declination | +85° 15.3′[1] |
Distance | 5,400 ly[2](1.66kpc) |
Apparent magnitude(V) | 10.0[3] |
Apparent dimensions (V) | 15′ |
Physical characteristics | |
Radius | 11.8ly |
Estimated age | 6.8 billion years[4] |
One of the oldest knownopen clusters | |
Other designations | Caldwell1,Cr6,Mel2[1] |
Associations | |
Constellation | Cepheus |
NGC 188(also known asCaldwell 1or thePolarissima Cluster[5]) is anopen clusterin the constellationCepheus.It was discovered byJohn Herschelin 1825. Unlike most open clusters that drift apart after a few million years because of the gravitational interaction of ourMilky Waygalaxy, NGC 188 lies far above the plane of the galaxy and is one of the most ancient of open clusters known, at approximately 6.8 billion years old.[4]
NGC 188 is very close to theNorth Celestial Pole,under five degrees away, and in the constellation of Cepheus at an estimated 5,000light-years' distance, this puts it slightly above the Milky Way's disc and further from the center of the galaxy than theSun.
References
[edit]- ^abc"NGC 188".SIMBAD.Centre de données astronomiques de Strasbourg.Retrieved2006-12-08.
- ^ Bonatto, C.; Bica, E.; Santos, J. F. C. Jr. (2005)."Spatial dependence of 2MASS luminosity and mass functions in the old open cluster NGC 188".Astronomy and Astrophysics.433(3): 917–929.arXiv:astro-ph/0502453.Bibcode:2005A&A...433..917B.doi:10.1051/0004-6361:20041113.
- ^ Clark, R. N. (1990).Visual Astronomy of the Deep Sky.Cambridge University Press.p. 287.Bibcode:1990vads.book.....C.ISBN978-0-521-36155-2.
- ^ab VandenBerg, D. A.; Stetson, P. B. (2004)."On the Old Open Clusters M67 and NGC 188: Convective Core Overshooting, Color-Temperature Relations, Distances, and Ages".Publications of the Astronomical Society of the Pacific.116(825): 997–1011.Bibcode:2004PASP..116..997V.doi:10.1086/426340.
- ^Stoyan, Ronald; Schurig, Stephan (2014).interstellarum Deep Sky Atlas.Erlangen: Cambridge University Press; Oculum-Verlag GmbH.ISBN978-1-107-50338-0.OCLC920437579.
External links
[edit]Media related toNGC 188at Wikimedia Commons
- NGC 188at SEDS NGC objects pages
- NGC 188at NightSkyInfo
- NGC 188 onWikiSky:DSS2,SDSS,GALEX,IRAS,Hydrogen α,X-Ray,Astrophoto,Sky Map,Articles and images
- NGC 188at theSIMBAD Astronomical Database.