The nebula is located in the Orion Sword and it is visible at naked eye as a second star in the sword from the top.
Visually the nebula appears greenish due to the better sensitivity of our eyes to the green light when dark adapted; the color is due to the hyonization of the oxigen due to radiation from the stars in the nebula.
In photo the nebula appears red due to the Hydrogen hyonization still due to the stars radiation. At the center of the nebula, in the overexposed area in teh picture, is visible, when observed visually, the Trapezium, a cluster of young and bright stars formed from the nebula gas.
M42 is about 420 light years far from us.
Photo Information:
Date: 4-1-2000
Place: Fremont Peak, Ca
Telescope: 80mm Short Tube Orion f/5 piggy back on Celestar 8 Deluxe
Camera: Olympus OM-2
Film: Kodak 400 PJM
Exposure: 15 minutes
Note: Poor seeing due to light pollution from Monterey Bay Area. The picture required Photoshop rework to make NGC 1977 ( the blue reflection nebula) barely visible.
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