Carbon dioxide, a potential fingerprint of life, has been discovered for the first time in the atmosphere of a planet orbiting another star.

A computer programme which could help identify and even translate messages from aliens in outer space has been developed by a British scientist. Dr John Elliott's program would compare an alien language to a database of 60 different languages in the world to search see if it has a similar structure.

Advanced extraterrestrial civilisations may be sending signals through space by "tickling" stars, new research suggests. The signalling would be the galactic equivalent of the internet.

An American snack-food company is beaming a commercial message towards a distant solar system. The publicity stunt is providing much needed funds to EISCAT European space station on the Norwegian island of Svalbard.

Nick Bostrom uses the "Doomsday Argument" to explain why finding lie on Mars would be a bad indicator of the future of humanity.

Advanced ground and space-based telescopes are discovering new planets around other stars almost daily, but an environmental scientist from England believes that even if some of those planets turn out to be Earth-like, the odds are very low they'll have intelligent inhabitants.

Tantalising traces of the building blocks of life have been spotted in nearby galaxies. However, working out the identity of these carbon-containing molecules, and when they became abundant, is proving tricky, say astronomers.

Mexico's Teotihuacan, once the center of a sprawling pre-Hispanic empire, is set to become the launch pad for an attempt to communicate with extraterrestrial life. Starting on Tuesday, enthusiasts from around the world will have a chance to submit text, images, video and sounds that reflect human nature to be included in the message.

For almost 50 years, SETI researchers have concentrated on detecting radio signals. However, researchers have come to think alien civilisations could also plausibly use laser light to communicate and have begun Optical SETI programs to detect these communications.

To the casual human listener, the love song of a humpback whale sounds magnificently free-flowing and improvised. But fresh mathematical analysis of the song shows there are complex grammatical rules. Using syntax, the whales combine sounds into phrases, which they further weave into hours-long melodies packed with information.