Professor Stephen Hawking, cosmologist: I think it is likely life exists elsewhere in the universe, but I think intelligent life must be very rare. Otherwise we would probably have been visited. I would be very wary of contacting another civilisation, but we have probably given the game away with the television signals we've been sending out for the last 50 years. But it will be some time before they can reply or get to us.

MYSTIC MEG, astrologer: Yes, I believe there is life on Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune. I am not sure about Pluto. On the warm side of Mercury the life-forms are circular and rarely need to move, their life is spent thinking. On the cold side, the beings are shaped like inverted triangles and take nourishment from algae-like substances. On Venus, the beings are most like humans, but have very long legs. Life-forms on Mars are like smaller versions of human forms and can change their colour to match the environment.

Patrick Moore, astronomer: I'm quite sure there's plenty of life in the universe: our sun is very run-of- the-mill. Given that there are a number of solar systems like our own, I imagine life is made up of the same materials as we are.

David Icke, writer and broadcaster: Somewhere between conception and birth we put on a genetic spacesuit that we take off when we die. Spending billions of dollars on trying to find alien life is ridiculous: it is here all around us all the time.

ELSIE OAKENSEN, retired teacher: I firmly believe in life on other planets. I saw a UFO in November 1978, when I drove underneath it. It was dumb-bell shaped, grey, smooth, with a red light at one end and a green light at the other. Under hypnosis I've also seen grey shapes with a silvery glow round the edges. That's why I'm so convinced life in the cosmos needn't look like a human being.

Steven Palmer, Space Invaders games installer: Aliens aren't real, they're only in films, and a good thing too. My own personal favourite is the knobbly one with the tentacles in the Quatermass film. If there is anything out there, we should leave it well alone.

Nicholas Stovin, solicitor: Extra-terrestial beings wouldn't look like us: I imagine they'd be a race of Norman Tebbits inhabiting a climate that's like a sauna. But there's definitely no other life in our solar system.

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