Editing Orion (constellation) (section)

===Deep-sky objects===
[[File:Orion Head to Toe.jpg|thumb|upright|This view brings out many fainter features, such as [[Barnard's Loop]].]]
Hanging from Orion's belt is his sword, consisting of the multiple stars θ1 and θ2 Orionis, called the [[Trapezium (astronomy)|Trapezium]] and the [[Orion Nebula]] (M42). This is a spectacular object that can be clearly identified with the naked eye as something other than a star. Using binoculars, its clouds of nascent stars, luminous gas, and dust can be observed. The Trapezium cluster has many newborn stars, including several [[brown dwarfs]], all of which are at an approximate distance of 1,500 light-years. Named for the four bright stars that form a [[trapezoid]], it is largely illuminated by the brightest stars, which are only a few hundred thousand years old. Observations by the [[Chandra X-ray Observatory]] show both the extreme temperatures of the main stars—up to 60,000 [[kelvin]]s—and the [[star formation|star forming regions]] still extant in the surrounding nebula.<ref name="objects">{{cite book |title = 300 Astronomical Objects: A Visual Reference to the Universe |last1=Wilkins |first1=Jamie |last2=Dunn |first2=Robert |publisher=Firefly Books |date=2006 |edition=1st |location=Buffalo, New York |isbn=978-1-55407-175-3}}</ref>

[[Messier 78|M78]] (NGC 2068) is a nebula in Orion. With an overall magnitude of 8.0, it is significantly dimmer than the Great Orion Nebula that lies to its south; however, it is at approximately the same distance, at 1600 light-years from Earth. It can easily be mistaken for a [[comet]] in the eyepiece of a telescope. M78 is associated with the [[variable star]] [[V351 Orionis]], whose magnitude changes are visible in very short periods of time.{{sfn|Levy|2005|pp=99–100}} Another fairly bright nebula in Orion is [[NGC 1999]], also close to the Great Orion Nebula. It has an integrated magnitude of 10.5 and is 1500 light-years from Earth. The variable star [[V380 Orionis]] is embedded in NGC 1999.{{sfn|Levy|2005|p=107}}

Another famous [[nebula]] is [[Index Catalogue|IC]] 434, the [[Horsehead Nebula]], near ζ Orionis. It contains a dark dust cloud whose shape gives the nebula its name.

[[NGC 2174]] is an [[emission nebula]] located 6400 light-years from Earth.

Besides these nebulae, surveying Orion with a small [[telescope]] will reveal a wealth of interesting deep-sky objects, including [[Messier 43|M43]], [[Messier 78|M78]], as well as multiple stars including [[Iota Orionis]] and [[Sigma Orionis]]. A larger telescope may reveal objects such as the [[Flame Nebula]] (NGC 2024), as well as fainter and tighter multiple stars and nebulae. [[Barnard's Loop]] can be seen on very dark nights or using [[long-exposure photography]].

All of these nebulae are part of the larger [[Orion molecular cloud complex]], which is located approximately 1,500 light-years away and is hundreds of light-years across. It is one of the most intense regions of stellar formation visible within the Milky Way Galaxy.