Have you ever heard of the Orion nebula? The Orion nebula is the brightest diffuse nebula in the sky. It can be seen with the naked eye in the constellation Orion. Orion (“The Great Hunter”) is one of the easiest constellations to identify in the winter sky.
On a clear night, starting around 9-10pm, look up in the southern sky, roughly halfway up and to the east, and you’ll see four bright stars forming a crude rectangle orientated somewhat vertically. Within the rectangle, near the middle, are three prominent stars arrayed in a row, equidistant, and dipping to the left. That is “Orion’s belt.” A couple stars are visible in a hazy area a bit below the middle of Orion’s belt. That is “his sword.” That hazy area there is the Orion nebula.
The Orion nebula is the closest and most active area of star formation in the Milky Way. It’s often compared to a stellar nursery or maternity ward. The dimensions of this thing are mind-boggling. It’s about 13 light years across and 1,500 light years away. That’s a “stone’s throw” in astronomical distance. In terms of actual miles, a light year represents 6 trillion miles.
Orion was a prominent feature in early mythology of many cultures. He was highly regarded as a hunter and a ladies’ man. The depth and extent of myths surrounding Orion can be illustrated by his being referenced in Homer’s Iliad and the Odyssey, and Paradise Lost.
A couple of myths about Orion have his death associated with a scorpion. For his eternal safety, the gods placed him in the heavens well away from the scorpion (Scorpius). He can be seen up there with his two dogs (Canus major and Canus minor) fighting Taurus the bull, and hunting Lepus the hare.
So, look up at Orion the next chance you get. Then when you find Orion focus in on the hazy area around his sword and take a good look at the Orion nebula and ponder this: The light you’re seeing has been traveling through interstellar space for some 1,500 years before finally landing in your eye!
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Further Reading
- The Orion Nebula is a starry nursery (EarthSky)
- Orion Nebula (NASA Hubble Space Telescope)
- Orion Nebula M42 — A Complete Guide (BBC SkyatNight Magazine)
