Messier 77 is a barred spiral galaxy located in the constellation Cetus, located 47 million light-years from Earth. Star formation regions are seen as streaks of red and blue in the spiral arms. The darker areas are dust lanes stretching across the galaxy's centre. Messier 77 belongs to a class of galaxies known as Seyfert galaxies, which have highly ionised gas surrounding an intensely active centre. Charles Messier, the 18th century French astronomer, catalogued over 100 galaxies and clusters. Through the telescopes available at the time, comets, nebulae, globular clusters and galaxies appeared just as faint, diffuse blobs. This image was taken by the NASA/ESA Hubble Space Telescope.