Spiral Galaxy · Cetus

M77 Cetus A

Magnitude
8.9
Season
Autumn
Difficulty
Moderate
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Imaging reference
Cetus A (M77) Spiral Galaxy

Observer's guide

About Cetus A

Cetus A (M77) is catalogued as a spiral galaxy in Cetus. Its J2000 position is RA 02:42:40.71, Dec -00:00:47.8, corresponding to 40.6696 degrees RA and -0.0133 degrees Dec. The local catalogue places it about 60,000,000 light-years away. Its referenced angular extent is approximately 5.5 by 5.09 arcminutes.

Observing tips

StarWatchr rates this as a moderate target at magnitude 8.9. It is associated with autumn observing, with midnight placement typically strongest around October. From 52 degrees north its theoretical meridian altitude is about 38 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 Sy2. SIMBAD records the morphology as SAb. A published radial velocity value is 1042.6 km/s. The SIMBAD record currently connects it to 4941 bibliographic references.

At roughly 5.5 arcminutes across, it benefits from a narrower field and adequate image scale. Use the listed 5.5 by 5.09 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 M77 are kept separate from practical observing guidance.

Coordinates (J2000/ICRS)
RA 40.669622° · Dec -0.013294°
SIMBAD classification
Sy2
Morphology
SAb
Angular extent
5.5′ × 5.09′
Position angle
27°
Surface brightness
21.15 mag/arcsec²
Radial velocity
1,042.57 km/s
Redshift
0.00348372
Linked bibliography
4,941 references
Best midnight placement
October
Observable latitude range
-90° 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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