NGC 1977, NGC 1975 and NGC 1973 "The Running Man Nebula" in Orion

This beautiful grouping of Reflection Nebulae (NGC 1977, NGC 1975, and NGC 1973) is often overlooked in favor of the substantial stellar nursery which lies about a half degree to the south, the Orion Nebula. William Herschel discovered NGC 1977 (southern section) in 1786, while Heinrich Louis d'Arrest first noted the two smaller regions NGC 1973 and NGC 1975 in 1862 and 1864, respectively. This nebula is also called "The Running Man Nebula" and Sharpless 279. Although the nebula is easy to see in a small telescope the "running man" dark lane area is difficult to pick out visually.

Like the Orion Nebula, the Running Man Reflection Nebula is associated with Orion's giant molecular cloud which lies about 1,500 light-years away. It appears blue because the blue light from the neighboring stars scatters more efficiently from nebula gas than does red light. There are also some small areas of emission nebulosity. The dark lanes are composed of mostly interstellar dust - fine needle-shaped carbon grains. Most of the reflected light is provided by the brightest star in the image above, 42 Orionis. This very young B-2 blue giant star is a member of the Orion OB1 stellar association. While there is no star cluster cataloged in this area there are over 100 bright young stars in the immediate area of the nebula. Although the number and density of young stars does not rival that found in the Orion Nebula, it is still one of the most active regions of ongoing star formation within 2,000 light years of the Sun.

NGC 1977 Constellation: Orion RA: 05h 35m 30.0s Dec: -04° 52' 00" Epoch 2000 Size (mins): 20.0' Classification: Reflection Nebula Dreyer's Description in the NGC:        "Very remarkable! 42 Orionis and nebula."	NGC 1975 RA: 05h 35m 24.0s Dec: -04° 41' 00" Epoch 2000 Size (mins): 10.0' Classification: Reflection Nebula Dreyer's Description in the NGC:     "Bright double star involved in nebula."
NGC 1973 RA: 05h 35m 06.0s Dec: -04° 44' 00" Epoch 2000 Size (mins): 5.0' Classification: Reflection Nebula Dreyer's Description in the NGC:        "Star of magnitude 8 or 9 involved in nebula."	42 Orionis RA: 05h 35m 23.164s Dec: -04° 50' 18.088" Epoch 2000 Magnitude: 4.58 Classification: Star, Spectral Class B2 III Description:        Brightest star involved in nebula.

George Normandin, KAS

March 24th, 2010