The sky around Orion Nebula at true scale, north up and east left, with stars to magnitude 8. The circles show the field of a low-power eyepiece and of 10×50 binoculars.
Visible to the naked eye as the middle "star" of the Sword. Binoculars show the glow; a small telescope resolves the four Trapezium stars that light it.
Orion Nebula is a diffuse nebula in Orion, 1,300 light-years away
Orion Nebula (M42, NGC 1976, LBN 974, MWSC 0582, Sh2-281) is a diffuse nebula in the constellation Orion, 1,300 light-years away. It shines at magnitude 4.0 and spans 1.1° × 1° of sky, about 25 light-years across. It is visible to the naked eye from a dark site, and it is highest in the evening sky in January.
Nebula: a cloud of gas and dust. Emission nebulae glow on their own, lit by ultraviolet light from hot young stars; reflection nebulae shine by starlight scattered from dust; dark nebulae block the light behind them.
Orion Nebula is Sh2-281 in the Sharpless catalog
Stewart Sharpless listed it in his catalog of H II regions (1959), drawn from the red and blue prints of the Palomar Sky Survey. He rated each region's brightness on a scale of 1 to 3; Sh2-281 is bright (class 3 of 3). It is also listed as LBN 974.
Finding Orion Nebula from Rigel
Orion Nebula lies 5.9° northeast of Rigel, the magnitude 0.2 star. Three fingers held at arm's length cover about 5°.
Orion Nebula is highest in the evening in January
The chart gives its height above the horizon at 9 pm through the year, from 60°N to 40°S. It can be seen from the whole southern hemisphere and north to about 85°N.
Orion Nebula is 1,300 light-years away
The light seen from Orion Nebula tonight left it about 1,300 years ago, around 726 AD. It ranks 8 of 109 by distance among the 110 Messier objects. Distance source: VLBA 388 pc (Kounkel 2017) / Gaia DR2 403 pc (Kuhn 2019).
