Planet-hunting scientist has high hopes of alien life Alien spacecraft and intergalactic life forms may have evaded detection by 200 professional telescopes scanning the universe every night - but they still could be 'out there', an award-winning scientist says. 'I think the chance of intelligent life elsewhere in the universe is very high, but still we have no evidence,' said Geoffrey Marcy, one of two scientists sharing the Shaw Prize this year. 'We don't have evidence but I suspect that there probably are [life forms] simply because our universe is so enormous,' said Professor Marcy, who shared the US$1 million prize with Professor Michel Mayor for their work in discovering planets outside the solar system. 'Our Milky Way galaxy has about 200 billion stars and there are hundreds of billions of galaxies similar to our galaxy,' he said at a presentation ceremony at the Convention and Exhibition Centre in Wan Chai last night. The pair will discuss the possibility of life on other planets in a lecture to be delivered at the University of Science and Technology today. The two scientists were the first to identify the orbits and masses of planets spinning around stars other than the Sun. 'We have detected more than 150 planets by indirect proof and we know we have a lot of planets,' said Professor Mayor. Professor Marcy said some planets they had discovered had temperatures similar to that which helped nurture life on Earth, between zero and 100 degrees Celsius. But Professor Mayor said not all the planets were pleasant. 'Some of these planets are awful worlds ... Imagine you have one planet turning around its star in only four days - you would have to pay your taxes every four days,' he said. Despite the possibility of life out there somewhere, Professor Marcy said there was 'no strong evidence to this day' of alien spacecraft visiting Earth. 'Two hundred professional telescopes cover the earth - northern hemisphere and southern hemisphere. Every night, the skies are scanned, but there has never been a detection of a UFO by professional astronomers. I think this non-detection is more significant than people will often voice.' The Shaw Prizes were established by Sir Run Run Shaw as an 'Asian Nobel'.