NGC 7142
AladinLite | |
Constellation | Cepheus |
Position equinox : J2000.0 |
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Right ascension | 21 h 45.2 m |
declination | + 65 ° 46.5 ′ |
Appearance
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classification | II 2 r |
Brightness (visual) | +9.3 mag |
Brightness (B-band) | +10.36 mag |
Angular expansion | 12 ' |
Brightest star | +12.1 mag |
Variable stars | V375 Cep |
Redness ( excess color E (BV)) | 0.397 mag |
Physical data
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Affiliation | Milky Way |
distance | approx. 6200 ly |
Metallicity [Fe / H] | +0.04 |
history | |
Discovered by | William Herschel |
Discovery time | October 18, 1794 |
Catalog names | |
NGC 7142 • C 2144 + 655 • OCl 241 • Cr 442 • Lund 1000 • GC 4709 • H VII-66 • h 2134 |
NGC 7142 is an open star cluster in the constellation Cepheus and has an angular extent of 12 'and an apparent magnitude of +9.3 mag. With an estimated age of around 4.5 billion years, it is one of the oldest known open star clusters. NGC 7142 was discovered by William Herschel on October 18, 1794 .