NGC 1973-75-77
Distance: 1460 Light Years

Right Ascension: 05 : 35.5 (hours : minutes)
Declination: -04 : 52 (degrees : minutes)

NGC 1977 is a complex nebula containing a diffuse reflection cloud and a bright HII region. It comprises the southern portion of S279, a more extended HII region 30 arc minutes north of the Orion Nebula. The stars of NGC 1977 are part of the Orion 1d subgroup, the youngest members of the Orion OB1 stellar association. NGC 1977 is bounded on the south by the extreme northern end of the Orion A Molecular cloud. The lone exciting star of NGC 1977 and the surrounding HII region, S279 is the B1 V star HD 37018 (42 Ori). This star and the other bright stars of NGC 1977 make up the youngest subgroup (subgroup d) of the Orion OB association. The stars in this region are between 2 and 4 million years old. The region of NGC 1977 represents the northern boundary of the OMC-2 and OMC-3 molecular cloud cores which is one of the most active sites of low and intermediate mass star formation known. A large number of energetic outflows, Herbig-Haro objects, and embedded protostars have been found in this region between NGC 1977 and M42-43 mostly at infrared wavelengths. The bright rim along the southwestern edge of NGC 1977 represents the interface of the nebula with its molecular cloud complex.