article_snippet: A nebula, which comes from the Latin word for ‘cloud’, is a region of gas and dust in space.
article_snippet: Some are the remains of dead stars that have expelled Some gas, whereas others are regions where new stars are being formed.
article_snippet: others are regions where new stars are being formed come in a variety of shapes and sizes.
article_snippet: There are four main types: planetary nebulae, reflection nebulae, absorption nebulae and emission nebulae.
article_snippet: The reddish glow comes from giant clouds of hydrogen, which are lit up by the intense ultraviolet light from the cluster of hot young stars in the middle of the picture.
article_snippet: The blue colouration is scattered light from these stars, while the brown darker features are huge clouds of cosmic dust, which absorb the light.