What are elliptical galaxies made of?
Elliptical galaxies have older stars than spiral galaxies. Not many new stars are made in elliptical galaxies because they have less dust and gas. Some elliptical galaxies are much bigger and heavier than spirals, but others are much smaller and lighter. The big ones are usually very bright, while the smaller ones are much fainter. Astronomers believe that because they have older stars, elliptical galaxies were made before spirals. The picture on the right (©AAO) shows the giant elliptical galaxy M87 (type E1). M87 is a very unusual galaxy. In 1918 astronomers found a huge jet of gas coming from the middle of the galaxy. Pictures from the Hubble Space Telescope now seem to show an enormous black hole in the middle.
