When is the best time to observe 3 Leonis?

3 Leonis is best observed from January through March, with peak visibility during February when it transits around midnight in the Northern Hemisphere.

Where is 3 Leonis located in the sky?

3 Leonis lies in the constellation Leo at right ascension 09h 28m and declination +08° 11′.

What telescope do I need to split 3 Leonis?

Splitting 3 Leonis requires an aperture of roughly 60 mm or larger — the components are separated by about 25.2″ at magnitudes near 5.7. The companion is about 5.4 magnitudes fainter, so glare from the primary — not separation — sets the minimum aperture. Larger apertures and steady seeing help resolve the pair cleanly.

3 Leonis — Double Star in Leo

Magnitude 5.7^m DoubleStar Leo Visible

Star Map + List + Plan Star Hop

Observe

1Physical Properties

Magnitude 5.71

Spectral Type K0III giant

Star Color Orange (B-V 1.04)

2Position & Identifiers

RA 09h 28m 29.2s

Dec +08° 11' 18.0"

Constellation Leo

HR 3755

HIP 46457

HD 81873

SAO 117718

Flamsteed 3 Leo

Double Cat 7391

SIMBAD

3How easy to split?

Primary 5.7 mag Companion 11.1 mag Separation 25.2″

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.	Hard+	Hard	V. hard+
150 mm Newton 150mm Newt.	Medium+	Medium	Medium
Celestron C8 (203 mm SCT) C8 203mm	Easy	Medium+	Medium

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 Jan – Mar (peak: Feb)

5Multiple Star System

Separation 25.2″

Companion Mag 11.1

Position Angle 80°

Star Colors A: Orange

Discoverer H 4 47

Notes

CPM.

Separation over time

Measured 1834 → 2015 (181 y)

Separation drift 25.0" → 25.2" (+0.20")

Rate +0.0011" / y

PA drift 78° → 80° (+2°, +0.011°/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.