When is the best time to observe 23 Orionis?

23 Orionis is best observed from November through January, with peak visibility during December when it transits around midnight in the Northern Hemisphere.

Where is 23 Orionis located in the sky?

23 Orionis lies in the constellation Orion at right ascension 05h 23m and declination +03° 33′.

What telescope do I need to split 23 Orionis?

Splitting 23 Orionis requires an aperture of roughly 60 mm or larger — the components are separated by about 32.0″ at magnitudes near 5.0. Larger apertures and steady seeing help resolve the pair cleanly.

23 Orionis — Double Star in Orion

Observable Double Star Good (58/100)

Sep: 32.0", Companion: mag 6.8

Magnitude 5.0^m DoubleStar Orion (Ori) Visible

Star Map + List + Plan

Observe

1Physical Properties

Magnitude 5.00

Spectral Type B1V

Star Color Blue (B-V -0.15)

2Position & Identifiers

RA 05h 22m 50.0s

Dec +03° 32' 40.0"

Constellation Orion (Ori)

HR 1770

HIP 25142

HD 35149

SAO 112697

Flamsteed 23 Ori

Double Cat 3962

SIMBAD

3How easy to split?

Primary 5.0 mag Companion 6.8 mag Separation 32.0″

Telescope	Bortle 3	Bortle 4	Bortle 5
80 mm refractor 80mm refr.	Easy	Easy	Easy
150 mm Newton 150mm Newt.	Easy	Easy	Easy
Celestron C8 (203 mm SCT) C8 203mm	Easy	Easy	Easy

Easy Medium Hard Very hard Impossible

Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs

4Visibility

Set a location in User Settings to see visibility data.

Best season Nov – Jan (peak: Dec)

5Multiple Star System

Separation 32.0″

Companion Mag 6.8

Position Angle 29°

Star Colors A: Blue B: White

Discoverer STF 696

Notes

Fixed. Secondary 7.17V, -0.12(B-V), -0.63(U-B), B5Vn, B8nnp or B3V, RV -58k/s, vsini 350k/s, optical.

Separation over time

Measured 1782 → 2019 (237 y)

Separation drift 32.8" → 32.0" (-0.80")

Rate -0.0034" / y

PA drift 31° → 29° (-2°, -0.008°/y)

Slow change over generations — observable in lifetime comparisons.

Measured from the WDS observational archive. No orbital solution has been derived — most likely the period is too long to fit an orbit to the available measurement arc.