In the night sky: Orion
In the night sky: Orion

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

Free course

In the night sky: Orion

2.1.2 What is a nebula?

Described image
Figure 4 Close-up of the Orion Nebula

The word nebula (plural, nebulae) comes from the Latin word meaning unclear, or literally ‘mist’. When we look at Orion with binoculars, or even the naked eye, if it is sufficiently dark, we can see that just above the tip of Orion’s sword is a fuzzy patch. This is the Orion Nebula.

Early astronomers described features in the night sky they could not resolve (i.e. could not get clear images of) as nebulae. We now know that the Orion Nebula, also known as M42, is actually a massive cloud of gas and dust. The gas is mainly hydrogen and helium, although there are significant amounts of other gases, including oxygen. The dust is mainly made from silicon and oxygen, similar to the minerals which make up many of the rocks on Earth.


Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to university level study, find out more about the types of qualifications we offer, including our entry level Access courses and Certificates.

Not ready for University study then browse over 900 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus