File:Iris_Nebula_-_NGC_7023_-_Caldwell_4.jpg · Wikimedia Commons · See Wikimedia Commons
Key facts
- Right ascension
- 21 01 35.60
- Declination
- +68 ° 10 ′ 10.0 ″
- Distance
- 1,300 ly
- Apparent dimensions v
- 18 ' x 18'
- Constellation
- Cepheus
- Radius
- 3 ly
- Designations
- NGC 7023 and LBN487, Caldwell 4, Cr 429
via Wikipedia infobox
Wikidata facts
- Distance from Earth
- 1400
- Image
- Iris1HunterWilson.jpg
Show 6 more facts
- right ascension
- 315.398333
- Commons category
- NGC 7023
- time of discovery or invention
- 1794-10-18
- catalog code
- GN 21.01.0
- apparent magnitude
- 7.20
- declination
- 68.1633
Sources (2)
via Wikidata · CC0
~8 min read
Article
The Iris Nebula (also known as NGC 7023 or Caldwell 4) is a bright reflection nebula located about 1,300 light years from Earth in the constellation of Cepheus. It is six light-years across. The nebula is illuminated by a magnitude +7.4 star designated HD 200775. It is six light-years across. The nebula was discovered in 1794 by Sir William Herschel, a astronomer, where it was then added to the New General Catalogue (NGC).
The nebula is a member of the Cepheus Flare. It is located near the Mira-type variable star T Cephei, and near the bright magnitude +3.23 variable star Beta Cephei (Alfirk). The designation NGC 7023 refers to the open cluster within the larger reflection nebula designated LBN 487.