M82 - The Cigar Galaxy

The galaxy Messier 82 is a fairly small galaxy, with a mass less than a tenth of the Milky Way's. At around 12 million light years away, Messier 82 is one of the best studied examples of a “starburst galaxy”. The spikes are “emission lines” from atoms and molecules which emit at very specific wavelengths – in this case carbon, carbon monoxide and ionised nitrogen. The relative brightnesses of the emission lines at different wavelengths tell astronomers information about the environment in which the molecules are sitting, such as the temperature of the gas.