NGC 891
Scientific overview
NGC 891 is a spiral galaxy in the constellation Andromeda. It shines at apparent magnitude 10.01 and spans about 13.03 arcminutes of sky.
Observation guide
Guidance follows standard observing practice, derived from the object's real magnitude and position. A dark, moonless sky always helps.
Location in the sky
Precision measurements
Distances and velocities from SIMBAD and redshift from NED · NGC 891
| Distance | 3.3920e+7 ly | SIMBAD · catalogued |
| Physical size (major axis) | 128,567 ly | SIMBAD · derived |
| Physical size (minor axis) | 29,897 ly | SIMBAD · derived |
| Redshift (z) | 0.001761 ± 1.0000e-5 | NED · catalogued |
| Radial velocity | 528 km/s | SIMBAD · measured |
| Right ascension (ICRS) | 35.637113 deg | SIMBAD · measured |
| Declination (ICRS) | 42.348319 deg | SIMBAD · measured |
Full field-level provenance
- Distance: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · mesDistance · dist · 2022MNRAS.511.6160K · distance indicator: T-F · catalogued value · source value 10.4 Mpc · retrieved 2026-07-11
- Physical size (major axis): Centre de données astronomiques de Strasbourg (CDS) · derived (OpenNGC angular size × SIMBAD distance) · physical size = angular size × distance (small-angle); angular size from OpenNGC, distance from SIMBAD mesDistance · derived · retrieved 2026-07-11
- Physical size (minor axis): Centre de données astronomiques de Strasbourg (CDS) · derived (OpenNGC angular size × SIMBAD distance) · physical size = angular size × distance (small-angle); angular size from OpenNGC, distance from SIMBAD mesDistance · derived · retrieved 2026-07-11
- Redshift (z): NASA/IPAC Extragalactic Database · NED · ObjectLookup · Redshift · 2000UZC...C......0F · catalogued value · NED quality SUN · retrieved 2026-07-11
- Radial velocity: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · rvz_radvel · 2009MNRAS.398..722T · direct catalogue measurement · retrieved 2026-07-11
- Right ascension (ICRS): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · ra · 2006AJ....131.1163S · direct catalogue measurement · retrieved 2026-07-11
- Declination (ICRS): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · dec · 2006AJ....131.1163S · direct catalogue measurement · retrieved 2026-07-11
Physical size is derived from the OpenNGC angular size and the catalogued distance (small-angle: size = angle × distance). Redshift is the object's measured redshift — a negative value is a blueshift (the galaxy is approaching, its motion dominated by local rather than cosmic expansion). Fields a source did not provide are omitted, never invented.
Other objects in Andromeda
| Object | Type | Mag | Size (′) |
|---|---|---|---|
| Andromeda GalaxyM 31 · NGC 224 | Spiral galaxy | 3.44 | 177.83 |
| NGC 7686NGC 7686 | Open cluster | 5.6 | 3.6 |
| NGC 752C 28 · NGC 752 | Open cluster | 5.7 | 39 |
| M 32M 32 · NGC 221 | Elliptical galaxy | 8.13 | 7.74 |
| M 110M 110 · NGC 205 | Elliptical galaxy | 8.15 | 16.22 |
| Copeland's Blue SnowballC 22 · NGC 7662 | Planetary nebula | 8.3 | 0.28 |
| NGC 956NGC 956 | Open cluster | 8.9 | 4.5 |
Sources
The primary and reference sources this topic draws on.
- OpenNGCOpenNGC (M. Verga) — NGC/IC, Messier, and Caldwell catalogue data
Openly-licensed deep-sky catalogue: object types, positions, magnitudes, sizes, morphology, and cross-identifiers.