is often referred to as The Hunter, is a prominent constellation located on the celestial equator and
visible throughout the world. It is one of the most conspicuous, and most recognizable constellations in the
night sky. Its name refers to Orion, a hunter in Greek mythology.
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Betelgeuse, known alternatively by its Bayer designation Alpha Orionis, is a massive M-type red supergiant star nearing the
end of its life. When it explodes it will even be visible during the day. It is the second brightest star in Orion, and is a
semiregular variable star. It serves as the "right shoulder" of the hunter it represents and is the eighth brightest star in the night sky.
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Rigel, which is also known as Beta Orionis, is a B-type blue supergiant that is the sixth brightest star in the night sky. Similar to
Betelguese, Rigel is fusing heavy elements in its core and will pass its supergiant stage soon (on an astronomical timescale), either
collapsing in the case of a supernova or shedding its outer layers and turning into a white dwarf. It serves as the left foot of Orion,
the hunter.
Hanging from Orion's belt is his sword, consisting of the multiple stars 01 and 02 Orionis, called the Trapezium and
the Orion Nebula (M42). This is a spectacular object which can be clearly identified with the naked eye as something
other than a star. Using binoculars, its swirling clouds of nascent stars, luminous gas, and dust can be observed.
Another famous nebula is IC 434, the Horsehead Nebula, near Zeta Orionis. It contains a dark dust cloud
whose shape gives the nebula its name.
Besides these nebulae, surveying Orion with a small telescope will reveal a wealth of interesting deep-sky objects,
including M43, M78, as well as multiple stars including Iota Orionis and Sigma Orionis. A larger telescope
may reveal objects such as Barnard's Loop and the Flame Nebula (NGC 2024), as well as fainter
and tighter multiple stars and nebulae.
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 in our galaxy.
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