Editing Orion (constellation) (section)

==Characteristics==
[[File:OrionCC.jpg|thumb|upright=1.2|left|The constellation of Orion, as it can be seen by the naked eye. Lines have been drawn.]]
Orion is bordered by Taurus to the northwest, Eridanus to the southwest, Lepus to the south, [[Monoceros (constellation)|Monoceros]] to the east, and Gemini to the northeast. Covering 594 [[square degree]]s, Orion ranks twenty-sixth of the 88 constellations in size. The constellation boundaries, as set by Belgian astronomer [[Eugène Joseph Delporte|Eugène Delporte]] in 1930, are defined by a polygon of 26 sides. In the [[equatorial coordinate system]], the [[right ascension]] coordinates of these borders lie between {{RA|04|43.3}} and {{RA|06|25.5}}, while the [[declination]] coordinates are between {{dec|22.87}} and {{dec|−10.97}}.<ref name="boundary">{{cite journal | title=Orion, Constellation Boundary | journal=The Constellations | publisher=International Astronomical Union | url=https://www.iau.org/public/themes/constellations/#ori | access-date=22 March 2013}}</ref> The constellation's three-letter abbreviation, as adopted by the [[International Astronomical Union]] in 1922, is "Ori".<ref name="pa30_469">{{cite magazine | last=Russell | first=Henry Norris | title=The New International Symbols for the Constellations | magazine=Popular Astronomy | volume=30 | pages=469–71 |bibcode=1922PA.....30..469R | date=1922}}</ref>

Orion is most visible in the evening sky from January to April,<ref>{{cite book|last1=Ellyard |first1=David|last2=Tirion |first2=Wil |date=2008 |title=The Southern Sky Guide|edition = 3rd|orig-year=1993|page=4|url=https://books.google.com/books?id=5Gn0ivM4EK0C&pg=PA4 |publisher=Cambridge University Press |location=Port Melbourne, Victoria |isbn= 978-0-521-71405-1}}</ref> winter in the Northern Hemisphere, and summer in the Southern Hemisphere. In the tropics (less than about 8° from the equator), the constellation [[Astronomical transit|transits]] at the [[zenith]].

In the period May–July (summer in the Northern Hemisphere, winter in the Southern Hemisphere), Orion is in the daytime sky and thus invisible at most latitudes. However, for much of [[Antarctica]] in the Southern Hemisphere's winter months, the Sun is below the [[horizon]] even at midday. Stars (and thus Orion, but only the brightest stars) are then visible at twilight for a few hours around local noon, just in the brightest section of the sky low in the North where the Sun is just below the horizon. At the same time of day at the South Pole itself ([[Amundsen–Scott South Pole Station]]), Rigel is only 8° above the horizon, and the Belt sweeps just along it. In the Southern Hemisphere's summer months, when Orion is normally visible in the night sky, the constellation is actually not visible in Antarctica because the sun does not set at that time of year south of the Antarctic Circle.<ref>{{cite web|url=http://www.dibonsmith.com/downunder.htm|title=A Beginner's Guide to the Heavens in the Southern Hemisphere|work=dibonsmith.com}}</ref><ref>{{cite web|url=http://skymaps.com/downloads.html|title=The Evening Sky Map Southern Hemisphere Edition|work=skymaps.com}}</ref>

In countries close to the equator (e.g., Kenya, Indonesia, Colombia, Ecuador), Orion appears overhead in December around midnight and in the February evening sky.