SkyEye: Monoceros

The Unicorn

Abbreviation:	Mon
Genitive:	Monocerotis
Origin:	Petrus Plancius
Fully Visible:	78°S – 78°N

Dutch astronomer Petrus Plancius (1552–1622) introduced this constellation on his 1612 celestial globe. Although the constellation is not easily distinguished by the naked eye, the celestial equator runs right through it which means it contains a great many star clusters and nebulae.

The constellation of Monoceros

Notable Features

Visible Named Stars
		The brightest star in the constellation, α Mon, is only fourth-magnitude. None of the visible stars in this constellation have an official name.
Other Interesting Stars
HD 45652	Lusitânia	This eighth-magnitude star is known to have at least one exoplanet. It is located north of the star 13 Mon.
HD 52265	Citalá	This star is known to have at least one exoplanet and is named for a large mountain fortress in Haiti. It is found between β Mon and δ Mon.
Deep Sky Objects
M50		This is an open cluster readily visible through binoculars. It is sixth-magnitude.
C46	Hubble's Variable Nebula	Although named for Edwin Hubble, this nebula was actually discovered in 1783 by William Herschel. The nebula is interesting in that it is both an emission nebula and a reflection nebula, thanks to the unusual interaction it has with an embedded variable star, R Mon.
C49	Rosette Nebula	This spectacular nebula is often photographed by amateur and professional alike. The entire complex has several New General Catalogue entries.
C50		This open cluster lies at the heart of the Rosette Nebula. The stars in the cluster are easily accessible through binoculars but long-exposure photography is necessary to reveal the surrounding nebula in all its glory. It is also known as NGC 2244.
C54		This open cluster was discovered by William Herschel in 1791.
NGC 2264	Cone Nebula, Christmas Tree Cluster	This open cluster is surrounded by nebulosity, including the dark finger that is called the Cone Nebula.
Meteor Shower Radiants
019 MON	Monocerotids	This minor shower peaks in early December.
246 AMO	α Monocerotids	Confusingly, the radiant for the α Monocerotid meteor shower lies just inside the border of the neighbouring constellation Canis Minor, not far from the bright star Procyon.