NGC 1023
Scientific overview
NGC 1023 is an elliptical galaxy in the constellation Perseus. It shines at apparent magnitude 9.47 and spans about 7.4 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 1023
| Distance | 3.3985e+7 ly | SIMBAD · catalogued |
| Physical size (major axis) | 73,156 ly | SIMBAD · derived |
| Physical size (minor axis) | 30,251 ly | SIMBAD · derived |
| Redshift (z) | 0.002121 ± 1.0000e-5 | NED · catalogued |
| Radial velocity | 637 km/s | SIMBAD · measured |
| Right ascension (ICRS) | 40.100056 deg | SIMBAD · measured |
| Declination (ICRS) | 39.06324 deg | SIMBAD · measured |
Full field-level provenance
- Distance: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · mesDistance · dist · 2016AJ....152...50T · catalogued value · source value 10.42 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 · 1999ApJS..121..287H · 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 · 2020yCat.1350....0G · direct catalogue measurement · retrieved 2026-07-11
- Declination (ICRS): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · dec · 2020yCat.1350....0G · 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 Perseus
| Object | Type | Mag | Size (′) |
|---|---|---|---|
| h Persei ClusterNGC 869 | Open cluster | 3.7 | 14.4 |
| chi Persei ClusterNGC 884 | Open cluster | 3.8 | 10.5 |
| California NebulaNGC 1499 | Nebula | 5 | 160 |
| M 34M 34 · NGC 1039 | Open cluster | 5.2 | 22.5 |
| NGC 1545NGC 1545 | Open cluster | 6.2 | 4.2 |
| NGC 1528NGC 1528 | Open cluster | 6.4 | 9.6 |
| NGC 1444NGC 1444 | Open cluster | 6.6 | 3.6 |
| NGC 1342NGC 1342 | Open cluster | 6.7 | 6.3 |
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.