Space

As far as we know, there is no form of life on any of the other planets in the Solar System. It was assumed that light, water and oxygen - as seen at the Earth's surface - were necessary to life and we know that none of the other planets have these surface conditions. However, in the last few years it has been found that some life-form need neither light nor oxygen as they live in a system which depends on sulphur from deep undersea volcanoes on conditions of extreme heat and pressure. So some scientists hope that life-forms might exist in similar extreme conditions elsewhere in the Solar System. Other possiblities that are being explored (or may be explored in the future) include Saturn's satellite Titan and Jupiter's satellite Europa, as well as several comets to see if they contain the basic materials to support life.