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

Monoceros Monoceros (Greek: Μονόκερως, "unicorn") is a faint constellation on the celestial equator. Its definition is attributed to the 17th-century Dutch cartographer Petrus Plancius. It is bordered by Orion to the west, Gemini to the north, ...

. Its location is a guide for sky navigation toward the Rosette Nebula. The white-hued primary component has a stellar classification of A5 IV, suggesting it is an aging

subgiant star A subgiant is a star that is brighter than a normal main-sequence star of the same spectral class, but not as bright as giant stars. The term subgiant is applied both to a particular spectral luminosity class and to a stage in the evolution o ...

. 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.Vizier catalog entry
/ref> The B component, at a separation of around 12.3", is a yellow-white hued

F-type main-sequence star An F-type main-sequence star (F V) is a main-sequence, hydrogen-fusing star of spectral type F and luminosity class V. These stars have from 1.0 to 1.4 times the mass of the Sun and surface temperatures between 6,000 and 7,600 K.Tables VII ...

of class F5 V and an apparent magnitude of 6.72.

References

{{DEFAULTSORT:Epsilon Monocerotis A-type subgiants F-type main-sequence stars Binary stars Monoceros (constellation) Monocerotis, Epsilon BD+04 1236 Monocerotis, 08 044769 030419 2298