Messier 43, also known as De Mairan’s Nebula, is a star-forming emission nebula within the Orion constellation. It was first described by Jean-Jacques d’Ortous de Mairan before 1731 and later cataloged by Charles Messier in 1769. This nebula is part of the larger Orion Molecular Cloud Complex and is separated from the Orion Nebula (M42) by a dark lane of dust. The nebula is illuminated by a massive star that shapes its dust and gas landscape.
Names and Catalog numbers
- Messier: M43
- NGC: NGC 1982
Position and the cosmic neighborhood
Messier 43 is situated near Orion’s Sword, below the three stars forming Orion’s Belt. It is part of the Orion Molecular Cloud Complex, a region rich in star formation. Nearby are other notable objects like the Horsehead Nebula and Flame Nebula, contributing to this vibrant stellar nursery.
Nice to Know
- Messier 43 is illuminated by the star HD 37061, a triple star system.
- The nebula’s H II region has a diameter of about 4.5 arcminutes.
- It was discovered before 1731 by Jean-Jacques d’Ortous de Mairan.
- Messier 43 is part of the Orion Molecular Cloud Complex, a significant star-forming region.
Brightness, distance and size
Messier 43 has an apparent magnitude of 9.0 and spans about 20 x 15 arcminutes in size. It is located approximately 1,300 light-years from Earth and measures around nine light-years across. This nebula can be observed with small telescopes due to its brightness and size.
