The Witch Head Nebula

Picture obtained from: Astronomy Picture of the Day  

        This week I will take a closer look at the photograph that was posted on Astronomy Picture of the Day. This picture was posted on January 17^th. One can see that this is a nebula and it is located in the constellation Orion. It is called the Witch Head nebula because many people are able to see the silhouette of a witches face. I however, cannot see the head. This nebula is close to 1000 light years away and has a blue appearance for two reasons. One of the reasons is because of Rigel’s blue color. The other reason is because the dust grains reflect blue light. The nebula is made of large amounts or gas and dust and may collapse to form another star or star system. The clouds can collapse under the influence of its own gravitational attraction. This process is known as Jeans instability. The cloud can reach this unstable point in a number of different ways. Stars that are nearby can cause winds that can compress gas and dust in the nebula, a shockwave from a supernova can cause the nebula to collapses and finally the collapse can occur when clouds collided together. When the nebula collapses a star forms. By studying nebulae like this one may be able to better understand the process of star formation.