Iris Nebula

{{Short description|Reflection nebula in the constellation Cepheus}}

{{Infobox nebula

| name = Iris Nebula

| image = Iris_Nebula_-_NGC_7023_-_Caldwell_4.jpg

| caption= Iris Nebula (NGC 7023 and LBN487)

| type = Reflection

| epoch = J2000.0

| ra = {{RA|21|01|35.60}}

| dec = {{DEC|+68|10|10.0}}

| dist_ly = 1,300

| appmag_v = 6.8

| size_v = 18' x 18'

| constellation = Cepheus

| radius_ly = 3

| absmag_v =

| notes =

| names = NGC 7023 and LBN487, Caldwell 4, Cr 429

}}

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.

The nebula, which shines at magnitude +6.8, is illuminated by a magnitude +7.4 star designated HD 200775.{{cite web|url=http://www.astrocruise.com/milky_way/N7023_05.htm|title=NGC 7023|last=Perkins|first=Philip|date=2005|publisher=astrocruise.com|access-date=2008-08-06|archive-url=https://web.archive.org/web/20080518053724/http://www.astrocruise.com/milky_way/N7023_05.htm|archive-date=2008-05-18|url-status=dead}} 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.{{Cite APOD|title=NGC 7023: The Iris Nebula|date=2004-11-04|access-date=2008-08-06}}