When is the best time to observe Ashlesha?

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

Where is Ashlesha located in the sky?

Ashlesha lies in the constellation Idra at right ascension 08h 47m and declination +06° 25′.

What telescope do I need to split Ashlesha?

Splitting Ashlesha requires an aperture of roughly 200 mm or larger — the components are separated by about 0.3″ at magnitudes near 3.4. Larger apertures and steady seeing help resolve the pair cleanly.

Ashlesha — Stella doppia in Idra

HIP 43109; Epsilon Hydrae; 11 Hydrae

Magnitudine 3.4^m DoubleStar Idra (Hya) Visibile

Mappa stellare + Lista + Piano

Su Ashlesha

Descrizione

Ashlesha, Epsilon Hydrae, is a multiple-star system about 129 light-years away in the constellation Hydra. The brightest component is a G-type giant of spectral class G7 III paired with an A-type subgiant companion at about 0.2 arcseconds — spectroscopically resolved but too close for visual splitting. The system shines at combined magnitude 3.38.

Consigli per l'osservazione

Ashlesha marks the head of Hydra, just south of the Cancer border. In small telescopes the pair appears as a single yellow-white point. A small, faint star (magnitude 10) at 3 arcseconds is sometimes observed as a visual companion but is actually a background star. Best observed January through May.

Storia

The name Ashlesha comes from Sanskrit, referring to one of the 27 lunar mansions (nakshatras) of traditional Indian astronomy. The nakshatra Ashlesha is associated with this region of Hydra. The IAU adopted the name in 2017.

Curiosità

Ashlesha is one of a small number of IAU-adopted star names drawn from Sanskrit and Indian astronomy — others include Revati and Chara. The nakshatra system divides the ecliptic into 27 equal lunar-mansion segments, anchoring many traditional Indian calendrical and astrological calculations.

Osservare

1Proprietà fisiche

Magnitudine 3.38

Intervallo 3.35 - 3.39

Tipo variabile BY:

Tipo spettrale G7III + A8III-IV: gigante

Colore della stella Arancione (B-V 0.68)

Distanza 129 ly

2Posizione e identificatori

RA 08h 46m 46.6s

Dec +06° 25' 08.0"

Costellazione Idra (Hya)

HR 3482

HIP 43109

HD 74874

SAO 117112

Bayer Epsilon

Flamsteed 11 Hya

Variable ID Eps Hya

Double Cat 6993

SIMBAD Wikipedia

3Facilità di osservazione

Accedi e configura la tua attrezzatura e località predefinita per vedere una riga personalizzata.

Attrezzatura	Bortle 3	Bortle 4	Bortle 5
Occhio nudo Occhio nudo	Facile	Facile	Medio+
Cercatore 50 mm Cercatore 50mm	Facile	Facile	Facile
Telescopio 150 mm 150mm telesc.	Facile	Facile	Facile

Facile Medio Difficile Molto difficile Impossibile

Bortle 3 = rurale · 4 = periferia · 5 = suburbano

4Visibilità

Imposta una località nelle impostazioni per vedere i dati di visibilità.

Periodo migliore Dec – Feb (peak: Jan)

5Sistema stellare multiplo Sextuple

Componenti 6 (sextuple)

ID componenti AB

Separazione 0.3″

Mag compagna 5.6

Sp compagna A8V

Angolo di posizione 126°

Colori delle stelle A: Arancione B: Bianco-giallo

Scopritore SP 1

Note

AB 3.8 G5III, 4.7 A8IV or F0V, 15.05y, a = 0.238". Speckle interferometric sep. 0.263-0.272", 1980-3. Combined mag., | colors. ABxC, 3.4, 7.8, dF7 at 3" from AB, 890y, a = 4.536". Component D, 12.7v at 19" from A, in hyperbolic orbit | about ABC, periastron distance, 29".

Separazione nel tempo

Periodo: 15.1 y Eccentricità: 0.654 Ora: 0.27", PA 166° -0.02" in 5 anni

Distanza apparente nel tempo, calcolata dagli elementi orbitali ORB6. Curve ripide indicano coppie in rapida evoluzione — osservatele finché sono separabili.