NGC 2903
Scientific overview
NGC 2903 is a spiral galaxy in the constellation Leo. It shines at apparent magnitude 8.91 and spans about 11.94 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 2903
| Distance | 2.9876e+7 ly | SIMBAD · catalogued |
| Physical size (major axis) | 103,765 ly | SIMBAD · derived |
| Physical size (minor axis) | 45,886 ly | SIMBAD · derived |
| Redshift (z) | 0.001834 ± 1.0000e-6 | NED · catalogued |
| Radial velocity | 536 ± 3 km/s | SIMBAD · measured |
| Right ascension (ICRS) | 143.042129 deg | SIMBAD · measured |
| Declination (ICRS) | 21.500831 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 9.16 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 · 2010MNRAS.404.1733S · catalogued value · NED quality UUN · retrieved 2026-07-11
- Radial velocity: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · rvz_radvel · 2022ApJS..261...21Y · 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 Leo
| Object | Type | Mag | Size (′) |
|---|---|---|---|
| M 66M 66 · NGC 3627 | Spiral galaxy | 8.92 | 10.28 |
| NGC 3521NGC 3521 | Barred spiral galaxy | 9.11 | 8.32 |
| M 96M 96 · NGC 3368 | Spiral galaxy | 9.21 | 8.26 |
| M 105M 105 · NGC 3379 | Elliptical galaxy | 9.27 | 4.89 |
| M 65M 65 · NGC 3623 | Spiral galaxy | 9.32 | 7.64 |
| NGC 3628NGC 3628 | Barred spiral galaxy | 9.45 | 11.04 |
| M 95M 95 · NGC 3351 | Spiral galaxy | 9.77 | 7.23 |
| NGC 3384NGC 3384 | Elliptical galaxy | 9.96 | 5.24 |
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.