When is the best time to observe 118 Tauri?

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

Where is 118 Tauri located in the sky?

118 Tauri lies in the constellation Taurus at right ascension 05h 29m and declination +25° 09′.

What telescope do I need to split 118 Tauri?

Splitting 118 Tauri requires an aperture of roughly 100 mm or larger — the components are separated by about 4.7″ at magnitudes near 5.5. Larger apertures and steady seeing help resolve the pair cleanly.

118 Tauri — Double Star in Taurus

Observable Double Star Excellent (63/100)

Sep: 4.7", Companion: mag 6.7

Magnitude 5.5^m DoubleStar Taurus (Tau) Visible

Star Map + List + Plan Star Hop

Observe

1Physical Properties

Magnitude 5.47

Spectral Type B8.5V

Star Color Blue-white (B-V -0.04)

Distance 233 ly

2Position & Identifiers

RA 05h 29m 16.5s

Dec +25° 09' 02.0"

Constellation Taurus (Tau)

HR 1821

HIP 25695

HD 35943

SAO 77201

Flamsteed 118 Tau

Double Cat 4068

SIMBAD

3How easy to split?

Primary 5.5 mag Companion 6.7 mag Separation 4.7″

Sign in and configure your equipment and default location to see a personalized row.

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 Triple C: optical

Components 3 (triple)

Component IDs AB

Separation 4.7″

Companion Mag 6.7

Companion Sp A0V

Position Angle 209°

Star Colors A: Blue-white B: Blue-white

Discoverer STF 716

Notes

AB binary, B is A0V; colors for combined light. C, 11.5v at 141".

Separation over time

Measured 1782 → 2022 (240 y)

Separation drift 4.9" → 4.7" (-0.20")

Rate -0.0008" / y

PA drift 193° → 209° (+16°, +0.067°/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.