Monday, 10 March 2014

NEBULA - M42 Orion

Arguably the most famous Messier object 

due to is brightness and position next to three collinear bright stars (RA 5h35m17s DEC -5°23'28'' ), the Orion nebula is located 1 300 light years away.

Events taking place on Earth when the light that made these pictures left the Orion nebula: the Iberian peninsula was being invaded by Ummayad's troops and finally ended with the conquest of the visigothic kingdom

M42 - The Orion Nebula

M42 - annotation

India was invaded at the same time by Muhhamad bin Qasim with 6 000 horses and a sultanat was established in Sindh.

This is the most prominent part of a much larger nebulosity that spreads through most of the constellation (the "Orion Molecular Cloud Complex"). This includes Barnard's Loop, the Horsehead nebula, M43, M78 and the Flame Nebula.

Despite its relative brightness, this nebula is not the easiest to photograph. The core is very bright and the dynamic range between the faint extensions and the core is immense. Several exposures need to be taken for different regions, then combined in order to see detail and avoid burnt whites.

The bright core contains an interesting asterism: the trapezium, four young stars. Resolving the 4 trapezium stars is a convenient resolving power test for instruments.