Iris Nebula

(Redirected from NGC 7023)

The Iris Nebula (also known as NGC 7023 and Caldwell 4) is a bright reflection nebula in the constellation Cepheus. The designation NGC 7023 refers to the open cluster within the larger reflection nebula designated LBN 487.

Iris Nebula
Reflection nebula
Iris Nebula (NGC 7023 and LBN487)
Observation data: J2000.0 epoch
Right ascension21h 01m 35.60s
Declination+68° 10 10.0″
Distance1,300 ly
Apparent magnitude (V)6.8
Apparent dimensions (V)18' x 18'
ConstellationCepheus
Physical characteristics
Radius3 ly
DesignationsNGC 7023 and LBN487, Caldwell 4, Cr 429
See also: Lists of nebulae

The nebula, which shines at magnitude +6.8, is illuminated by a magnitude +7.4 star designated HD 200775.[1] It is located near the Mira-type variable star T Cephei, and near the bright magnitude +3.23 variable star Beta Cephei (Alfirk). It lies 1,300 light-years away and is six light-years across.[2]

Notes

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Map showing location of NGC 7023
  1. ^ Perkins, Philip (2005). "NGC 7023". astrocruise.com. Archived from the original on 2008-05-18. Retrieved 2008-08-06.
  2. ^ Nemiroff, R.; Bonnell, J., eds. (2004-11-04). "NGC 7023: The Iris Nebula". Astronomy Picture of the Day. NASA. Retrieved 2008-08-06.

References

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  • Pasachoff, Jay M. (2000). "Atlas of the Sky". Stars and Planets. New York, New York: Peterson Field Guides. pp. 578 pg. ISBN 978-0-395-93432-6.
  • Caldwell-Moore, Sir Patrick (2003). Firefly Atlas of the Universe. Firefly Books Limited. ISBN 978-1-55297-819-1.
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