Monoceros is a constellation lying on the celestial equator. It was created by the Dutch astronomer Petrus Plancius in the 17th century. Monoceros is Greek for "unicorn." Plancius gave it the name because the mythical single-horned animal appears in the Bible several times.
The constellation Monoceros occupies an area of 482 square degrees and contains ten stars with known planets. It can be seen at latitudes between +75° and -85° and is best visible at 9 p.m. during the month of February.
Monoceros is a rather faint constellation, with only a few stars visible to the naked eye. The brightest star in the constellation is 
alpha Monocerotis, with a visual magnitude of 3.93. It is approximately 144 light-years distant. 
gamma Monocerotis, the second brightest star, has a magnitude of 3.98.
beta Monocerotis is a triple star, with three components forming a fixed triangle. It can be spotted in a small telescope. German astronomer Friedrich Wilhelm Herschel, who discovered the star system in 1781, called it "one of the most beautiful sights in the heavens."
epsilon Monocerotis is a fixed double star composed of a bluish white primary and a yellow companion star. The stars sometimes appear golden and lilac in colour, depending on the telescope.
Another notable star is 
Plaskett’s Star, a binary star with a mass about 100 times that of the Sun. It is one of the most massive double stars known, with two giants orbiting each other at about half the distance between the Earth and the Sun.
Monoceros contains several interesting deep sky objects. NGC 2264 contains four objects that are about 2,600 light-years distant: the Cone Nebula, the Christmas Tree Cluster, Snowflake Cluster and the Fox Fur Nebula.
The Cone Nebula, a long, cone-shaped dust cloud, is a region of star formation surrounding the Christmas Tree Cluster, an open cluster containing about 40 stars that form the shape of a fir tree. The Snowflake Cluster is composed of newborn stars lying in cloud of thick dust, lined up in a configuration that resembles the pattern of a snowflake. The Fox Fur Nebula got its name because it has regions of dust and gas glowing red and resembling the head of a fox stole.
The star 
S Monocerotis, a massive variable binary with a blue-white dwarf for the primary component, is located at the centre of NGC 2264. It is actually a multiple star system, with several other faint components.
The Rosette Nebula, located near 
epsilon Monocerotis, is a large diffuse nebula illuminated by young, hot, blue stars. Like the Fox Fur Nebula, it has a red glow caused by emission of hydrogen. It is also a star-forming region, about 5,200 light-years from Earth. It has a diameter spanning 90 light-years and its NGC designations are NGC 2237, NGC 2238, NGC 2239, NGC 2244 and NGC 2246. The Rosette Nebula is usually referred to as NGC 2237. NGC 2244 is an open cluster of stars formed in the nebula.
NGC 2323 (Messier 50) is an open cluster of stars resembling the shape of a heart. It is approximately 3,000 light-years distant.
Monoceros belongs to the Orion family of constellations, along with Orion
, Canis Major
, Canis Minor
Constellations directly bordering Monoceros are Canis Major
, Canis Minor