Lower Sword
Scientific overview
Lower Sword is a cluster with nebulosity in the constellation Orion. It shines at apparent magnitude 2.5 and spans about 9.3 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 · NGC 1980
| Distance | 1,251 ly | SIMBAD · catalogued |
| Physical size (major axis) | 3.384648 ly | SIMBAD · derived |
| Radial velocity | 26.68 ± 0.15 km/s | SIMBAD · measured |
| Right ascension (ICRS) | 83.81 deg | SIMBAD · measured |
| Declination (ICRS) | -5.923889 deg | SIMBAD · measured |
Full field-level provenance
- Distance: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · mesDistance · dist · 2022ApJ...931..156P · catalogued value · source value 383.6 pc · 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
- Radial velocity: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · rvz_radvel · 2021A&A...647A..19T · direct catalogue measurement · retrieved 2026-07-11
- Right ascension (ICRS): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · ra · 2021A&A...647A..19T · direct catalogue measurement · retrieved 2026-07-11
- Declination (ICRS): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · dec · 2021A&A...647A..19T · 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). This is a Galactic object: its Doppler shift is shown as a radial velocity, not a cosmological redshift. Fields a source did not provide are omitted, never invented.
Other objects in Orion
| Object | Type | Mag | Size (′) |
|---|---|---|---|
| Great Orion NebulaM 42 · NGC 1976 | Cluster with nebulosity | 4 | 90 |
| Upper SwordNGC 1981 | Cluster with nebulosity | 4.2 | 9 |
| NGC 1788NGC 1788 | Reflection nebula | 5.8 | 2 |
| NGC 2169NGC 2169 | Open cluster | 5.9 | 7.2 |
| NGC 1662NGC 1662 | Open cluster | 6.4 | 13.8 |
| NGC 2175NGC 2175 | Cluster with nebulosity | 6.8 | 5.4 |
| NGC 1973NGC 1973 | Nebula | 7 | 5 |
| NGC 1975NGC 1975 | Nebula | 7 | 10 |
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.