Several thousand million stars, mainly old and yellow, make up this elliptical galaxy, which is 12 million light years away. Most elliptical galaxies have little gas and dust but Centaurus A (NGC 5128) is surrounded by a dense band of dust that blocks out the light from the stars behind. This is the remains of a dusty spiral galaxy that Centaurus A (NGC 5128) absorbed about a billion years ago in a merger that made the galaxy one of the strongest sources of cosmic radio waves.