Monoceros

Monoceros

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List of stars in Monoceros
Abbreviation:	Mon
Genitive:	Monocerotis
Symbology:	the Unicorn
Right ascension:	7.15 h
Declination:	−5.74°
Area:	482 sq. deg. (35th)
Main stars:	4
Bayer/Flamsteed stars:	28
Stars known to have planets:	4
Bright stars:	0
Nearby stars:	2
Brightest star:	α Monocerotis (3.93m)
Nearest star:	Luyten's Star (12.4 ly)
Messier objects:	1
Meteor showers:	December Monocerids Alpha Monocerids
Bordering constellations:	Canis Major Canis Minor Gemini Hydra Lepus Orion Puppis
Visible at latitudes between +75° and −85° Best visible at 21:00 (9 p.m.) during the month of February

Monoceros (IPA: /məˈnɒsərəs/, Greek: Μονόκερος) is a faint constellation on the winter night sky, surrounded by Orion to the west, Gemini to the north, Canis Major to the south and Hydra to the east. Other bordering constellations include Canis Minor, Lepus and Puppis.

Notable features

Monoceros is an almost invisible constellation, with only a few fourth magnitude stars. Alpha Monocerotis has a visual magnitude of 3.93, slightly brighter than Gamma Monocerotis, which has a visual magnitude of 3.98.

However, Monoceros does have some interesting features to observe with the aid of a small telescope. Beta Monocerotis is an impressive triple star system, the three stars form a triangle which seems to be fixed. The visual magnitudes of the stars are 4.7, 5.2 and 6.1. William Herschel discovered it in 1781 and commented it as 'one of the most beautiful sights in the heavens'.

Epsilon Monocerotis is a fixed binary, with visual magnitudes of 4.5 and 6.5.

S Monocerotis, or 15 Monocerotis, is a bluish white variable star and is located at the center of NGC 2264. However the variation of its magnitude is not too great. It has a companion star of visual magnitude 8.

V838 Monocerotis had an outburst starting on January 6, 2002.

Notable deep sky objects

Monoceros contains many clusters and nebulae, most notable among them;

• M50, an open cluster
• The Rosette Nebula (NGC 2237-9,46), a diffuse nebula
• The Christmas Tree Cluster and associated Cone Nebula (NGC 2264)

History

Monoceros is a modern constellation, charted by Jakob Bartsch as Unicornus in his star chart of 1624 and once supposed to have been named by the Dutch astronomer and theologian Petrus Plancius in 1613; but Heinrich Wilhelm Olbers and Ludwig Ideler indicate the constellation is actually much older, as "the second horse south of the Twins and the Crab", appearing in works as early at 1564, and Joseph Scaliger is reported to have found it on an ancient Persian sphere.

References

• Ridpath, Ian; Wil Tirion (2007). Collins Stars and Planets Guide. London: HarperCollins. ISBN 978-0-00-725120-9. 

External links

Wikimedia Commons has media related to:

Monoceros

• The Deep Photographic Guide to the Constellations: Monoceros
• http://www.dibonsmith.com/mon_con.htm
• http://www.astronomical.org/constellations/mon.html
• Star Tales – Monoceros

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