Earth's previous attempts to contact intelligent, extraterrestrial life could be too disorganised or cryptic for non-human beings to decode, US physicists have reported. The researchers suggested that a protocol be developed to improve the likelihood that messages would be understood that would include constraints and guidelines for signal encoding, message length, information content.

If the sun's gravity could be used to create a giant telescope, people could send and receive intensely magnified signals that could allow us to call an alien civilization, some researchers propose.

As the citizens of Planet Earth strive ever more enthusiastically to reach E.T., some experts say numerous messages zipping through the cosmos are confusing or little more than space spam. Others ask who has the right to represent our world to the galaxy -- or question the wisdom of bellowing out our presence in what may be a hostile neighbourhood.

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.

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.

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.

The search for extraterrestrial intelligence (SETI) could be taking the wrong approach. Instead of listening for alien radio broadcasts, a better strategy may be to look for giant structures placed in orbit around nearby stars by alien civilisations.

A new study suggests it is more energy efficient to communicate across interstellar space by sending physical material?a sort of message in a bottle?than beams of electromagnetic radiation. Currently, the bulk of the effort to identify extraterrestrial civilizations has focused on the electromagnetic spectrum.