Not only is the Orion Nebula one of the most spectacular of nebulae, but it is
also one of the easiest to locate, lying in the middle of the conspicuous
Sword of Orion. It is in fact the brightest
nebula in the sky.
Though not apparent to the naked eye, Orion contains a gigantic dark cloud of matter,
the largest such cloud known in the Milky Way Galaxy. Within the
Orion Molecular Cloud,
new stars are forming, a process that creates a pocket or 'bubble' around the newly
The quadruple star known as the Trapezium is one of these young systems, thought to be little
more than 100,000 years old. It started to form just within the edge of the cloud, and its
bubble has burst through that edge, leaving us with an illuminated view of the cloud's interior:
the Orion Nebula.
The nebula's reddish colouration betrays the predominance of ionised hydrogen in the parent
cloud, but more complex molecules such as carbon monoxide have also been detected. Stellar
formation in this region of space is still in progress, and infrared observation suggests
that at least two new stars will shortly come into existence.