When is the best time to observe Psi Orionis?

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

Where is Psi Orionis located in the sky?

Psi Orionis lies in the constellation Orion at right ascension 05h 27m and declination +03° 06′.

What telescope do I need to split Psi Orionis?

Splitting Psi Orionis requires an aperture of roughly 100 mm or larger — the components are separated by about 3.0″ at magnitudes near 4.6. The companion is about 4.0 magnitudes fainter, so glare from the primary — not separation — sets the minimum aperture. Larger apertures and steady seeing help resolve the pair cleanly.

Psi Orionis — Double Star in Orion

HIP 25473; Psi2 Orionis; 30 Orionis

Observable Double Star Good (53/100)

Sep: 3.0", Companion: mag 8.6

Magnitude 4.6^m DoubleStar Orion (Ori) Visible

Star Map + List + Plan

Observe

1Physical Properties

Magnitude 4.59

Range 4.55 - 4.61

Period 2.5 days

Variable Type E/D

Spectral Type B2IV subgiant

Star Color Blue (B-V -0.21)

2Position & Identifiers

RA 05h 26m 50.2s

Dec +03° 05' 44.0"

Constellation Orion (Ori)

HR 1811

HIP 25473

HD 35715

SAO 112775

Bayer Psi2

Flamsteed 30 Ori

Variable ID Psi Ori

Double Cat 4039

SIMBAD Wikipedia

3How easy to split?

Primary 4.6 mag Companion 8.6 mag Separation 3.0″

Telescope	Bortle 3	Bortle 4	Bortle 5
80 mm refractor 80mm refr.	V. hard+	V. hard+	V. hard+
150 mm Newton 150mm Newt.	Hard+	Hard+	Hard+
Celestron C8 (203 mm SCT) C8 203mm	Medium	Medium	Medium

Easy Medium Hard Very hard Impossible

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

4Visibility

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Best season Nov – Jan (peak: Dec)

5Light Curve

6Multiple Star System Triple C: optical

Components 3 (triple)

Component IDs AB

Separation 3.0″

Companion Mag 8.6

Position Angle 328°

Star Colors A: Blue B: Yellow-white

Discoverer KNT 3

Notes

AB about 6300y. B, 10.3V, vsini 96k/s. C, 12.3v at 83", optical.

Separation over time

Measured 1863 → 2022 (159 y)

Separation drift 2.8" → 3.0" (+0.20")

Rate +0.0013" / y

PA drift 322° → 328° (+6°, +0.038°/y)

Essentially fixed on human timescales — the same view your grandchildren will see.

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.