Reflection Nebula · Cepheus

C4 Iris Nebula

Magnitude
6.8
Season
Summer
Difficulty
Hard
Star-hop chart
C40.0° field0° rotation
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Iris Nebula (C4) Reflection Nebula

Observer's guide

About Iris Nebula

Iris Nebula (C4) is catalogued as a reflection nebula in Cepheus. Its J2000 position is RA 21:01:48, Dec +68:12:00, corresponding to 315.4037 degrees RA and 68.1633 degrees Dec. The local catalogue places it about 1,400 light-years away. No consistent angular diameter is available in the source record.

Observing tips

StarWatchr rates this as a hard target at magnitude 6.8. It is associated with summer observing, with midnight placement typically strongest around August. From 52 degrees north its theoretical meridian altitude is about 73.8 degrees; local horizons and the live altitude chart determine the practical window.

A small telescope under reasonably dark skies is a good starting point; use the live altitude chart to choose its highest point.

What to expect

The SIMBAD classification for the matched source is OpC. The SIMBAD record currently connects it to 741 bibliographic references.

Confirm the framing in the live sky atlas before choosing a field of view. Use the listed unknown arcminute extent to check framing, and treat catalogue magnitude as integrated brightness rather than a direct measure of visual contrast.

Sourced catalogue data

Scientific record

Measurements for C4 are kept separate from practical observing guidance.

Coordinates (J2000/ICRS)
RA 315.40375° · Dec 68.163333°
SIMBAD classification
OpC
Linked bibliography
741 references
Best midnight placement
August
Observable latitude range
-21.8° to 90°

Source: SIMBAD astronomical database (CDS, Strasbourg) (ODbL; checked 2026-08-09). Catalogue values may change when new measurements are published.

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