When is the best time to observe 17 Comae Berenices?

17 Comae Berenices is best observed from February through April, with peak visibility during March when it transits around midnight in the Northern Hemisphere.

Where is 17 Comae Berenices located in the sky?

17 Comae Berenices lies in the constellation Coma Berenices at right ascension 12h 29m and declination +25° 55′.

What telescope do I need to split 17 Comae Berenices?

Splitting 17 Comae Berenices requires an aperture of roughly 60 mm or larger — the components are separated by about 146.4″ at magnitudes near 5.3. Larger apertures and steady seeing help resolve the pair cleanly.

17 Comae Berenices — Double Star in Coma Berenices

Observable Double Star Good (49/100)

Sep: 146.4", Companion: mag 6.6

Magnitude 5.2–5.4^m DoubleStar Coma Berenices (Com) Visible

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Observe

1Physical Properties

Magnitude 5.29

Range 5.23 - 5.4

Period 5.1 days

Variable Type Alpha2 CVn (Magnetic Rotating)

Spectral Type A1IVp supergiant

Star Color Blue-white (B-V -0.05)

Distance 155 ly

2Position & Identifiers

RA 12h 28m 54.7s

Dec +25° 54' 46.0"

Constellation Coma Berenices (Com)

HR 4752

HIP 60904

HD 108662

SAO 82330

Flamsteed 17 Com

Variable ID AI Com

Double Cat 8568

SIMBAD

3How easy to split?

Primary 5.3 mag Companion 6.6 mag Separation 146.4″

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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

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Best season Feb – Apr (peak: Mar)

5Light Curve

6Multiple Star System Triple D,E,F: optical

Components 3 (triple)

Component IDs AB

Separation 146.4″

Companion Mag 6.6

Position Angle 251°

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

Discoverer STFA 21

Notes

CPM with HR 4751.

Separation over time

Measured 1836 → 2018 (182 y)

Separation drift 145.3" → 146.4" (+1.10")

Rate +0.0060" / y

PA drift 251° → 251° (+0°, +0.000°/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.