Iris Nebula

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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'
Physical characteristics
Radius3 ly
DesignationsNGC 7023 and LBN487, Caldwell 4
See also: Lists of nebulae

The Iris Nebula, also known as NGC 7023 and Caldwell 4, is a bright reflection nebula and Caldwell object in the constellation Cepheus. NGC 7023 is actually the cluster within the nebula, LBN 487, and the nebula is lit by a magnitude +7 star, SAO 19158.[1] It shines at magnitude +6.8. It is located near the Mira-type variable star T Cephei, and near the bright magnitude +3.23 variable star Beta Cephei (Alphirk). It lies 1,300 light-years away and is six light-years across.[2]


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External links[edit]

RGB image of The Iris Nebula NGC 7023 taken with a 5" apochromatic refractor and a DSLR camera
Map showing location of NGC 7023 (Roberto Mura)