When is the best time to observe Alya?

Alya is best observed from May through July, with peak visibility during June when it transits around midnight in the Northern Hemisphere.

Where is Alya located in the sky?

Alya lies in the constellation Serpens at right ascension 18h 56m and declination +04° 12′.

What telescope do I need to split Alya?

Splitting Alya requires an aperture of roughly 60 mm or larger — the components are separated by about 22.4″ at magnitudes near 4.6. Larger apertures and steady seeing help resolve the pair cleanly.

Alya — Double Star in Serpens

HIP 92946; Theta1 Serpentis; 63 Serpentis

Observable Double Star Excellent (72/100)

Sep: 22.4", Companion: mag 4.9

Magnitude 4.6–4.7^m DoubleStar Serpens (Ser) Visible

Star Map + List + Plan

Observe

1Physical Properties

Magnitude 4.62

Spectral Type A5V

Star Color Yellow-white (B-V 0.17)

Distance 109 ly

2Position & Identifiers

RA 18h 56m 13.2s

Dec +04° 12' 13.0"

Constellation Serpens (Ser)

HR 7141

HIP 92946

HD 175638

SAO 124068

Bayer Theta1

Flamsteed 63 Ser

Double Cat 11853

SIMBAD Wikipedia

3How easy to split?

Primary 4.6 mag Companion 4.9 mag Separation 22.4″

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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 May – Jul (peak: Jun)

5Multiple Star System Triple C: optical

Components 3 (triple)

Component IDs AB

Separation 22.4″

Companion Mag 4.9

Companion Sp A5Vn

Position Angle 106°

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

Discoverer STF2417

Notes

Binary with HR 7142.

Separation over time

Measured 1755 → 2019 (264 y)

Separation drift 22.1" → 22.4" (+0.30")

Rate +0.0011" / y

PA drift 106° → 106° (+0°, +0.000°/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.