This extraordinary image, taken with the Hubble Space Telescope, shows a mini-spiral deep inside NGC 7252. The spiral is composed of gas and young stars and looks very much like a spiral galaxy. Compare this picture with the spiral galaxy NGC 6946, which is about 70,000 light years across. This entire image is less than half that size; the size of the mini-spiral itself is still unresolved.
Notice the many globular clusters here. Most have a diameter of about 60 light years, roughly the same size as the globular clusters that orbit the Milky Way. The stars in the clusters are thought to be between 50 and 500 million years old, so the globular clusters probably formed when the two galaxies merged to form NGC 7252.
