False-colour optical image of the radio galaxy Centaurus A (NGC 5128), showing the great lane of dust which bisects it. Centaurus A is basically a giant elliptical galaxy encircled by a rotating disc of gas and dust which, seen edge-on, forms the dust lane. Radio maps reveal two enormous radio lobes extending fully 10 degrees across the sky and lying at right angles to the dust lane. A giant cluster of hot stars and gas, more luminous than many entire galaxies, lies at the galaxy's centre. Within this, so many astronomers believe, is a black hole, the central engine" powering the galaxy. Located some 16 million light years away, Centaurus A is the nearest active galaxy to Earth."