Epsilon Monocerotis

ε Monocerotis A

Location of ε Monocerotis (circled red)
Observation data Epoch J2000      Equinox J2000
Constellation	Monoceros
Right ascension	06h 23m 46.08471s
Declination	4° 35′ 34.3153″
Apparent magnitude (V)	4.39
Characteristics
Spectral type	A5IV
U−B color index	+0.14
B−V color index	+0.20
Astrometry
Radial velocity (Rv)	+13.10 km/s
Proper motion (μ)	RA: -22.06 mas/yr Dec.: +10.91 mas/yr
Parallax (π)	26.67 ± 0.90mas
Distance	122 ± 4 ly (37 ± 1 pc)
Absolute magnitude (MV)	1.52
Details
Mass	2.04 M☉
Radius	2.5 R☉
Luminosity	25 L☉
Surface gravity (log g)	3.95 cgs
Temperature	7,923 K
Metallicity [Fe/H]	-0.11 dex
Rotational velocity (v sin i)	149 km/s
Other designations
8 Monocerotis A, 8 Mon A, BD+04 1236, CCDM J06237+0436A, FK5 244, GC 8240, HIP 30419, HR 2298, HD 44769, SAO 113810, WDS J06238+0436A
Database references
SIMBAD	data

ε Monocerotis, Latinised as Epsilon Monocerotis, is the Bayer designation of a binary star in the constellation Monoceros.

Its location is guide for sky navigation toward Rosette nebula

The primary is a class A5IV (white subgiant) star in the constellation Monoceros. Its apparent magnitude is 4.39 and it is approximately 122 light years away based on parallax. It is reportedly a spectroscopic binary with a period around 331 days.

The B component, at a separation of around 12.3", is a class F5V (yellow-white dwarf) star, with an apparent magnitude of 6.72.