Open Cluster · Lacerta

C16 NGC 7243

Magnitude
6.4
Season
Summer
Difficulty
Very Easy
Star-hop chart
C160.0° field0° rotation
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Imaging reference
NGC 7243 (C16) Open Cluster

Observer's guide

About NGC 7243

NGC 7243 (C16) is catalogued as an open cluster in Lacerta. Its J2000 position is RA 22:15:09, Dec +49:52:30, corresponding to 333.7875 degrees RA and 49.83 degrees Dec. The local catalogue places it about 2,500 light-years away. Its referenced angular extent is approximately 30.6 by 30.6 arcminutes.

Observing tips

StarWatchr rates this as a very easy target at magnitude 6.4. It is associated with summer observing, with midnight placement typically strongest around August. From 52 degrees north its theoretical meridian altitude is about 87.8 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. A published radial velocity value is -10.2 km/s. The SIMBAD record currently connects it to 137 bibliographic references.

Its roughly 30.6 arcminute span suits a medium field of view. Use the listed 30.6 by 30.6 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 C16 are kept separate from practical observing guidance.

Coordinates (J2000/ICRS)
RA 333.7875° · Dec 49.8300°
SIMBAD classification
OpC
Angular extent
30.6′ × 30.6′
Position angle
Radial velocity
-10.16 km/s
Redshift
-0.00003391
Linked bibliography
137 references
Best midnight placement
August
Observable latitude range
-40.2° 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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24-hour altitude profile

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