NGC 7142

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Open star cluster
NGC 7142
AladinLite
Constellation Cepheus
Position
equinox : J2000.0
Right ascension 21 h 45.2 m
declination + 65 ° 46.5 ′
Appearance

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

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 .

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