Operating on money and equipment scrounged from the public and from Silicon Valley millionaires, and on the stubborn strength of their own dreams, a band of astronomers recently restarted one of the iconic quests of modern science, the search for extraterrestrial intelligence — SETI, for short — which had been interrupted last year by a lack of financing.

Extraterrestrial civilisations could give themselves away by the night-time glow of their cities. And if there is one lurking in the outer reaches of our solar system, we are ready to find it.

Astronomers announced Monday that they had taken E.T. off hold and resumed searching for radio signals from extraterrestrial civilizations with a set of radio telescopes in Hat Creek, Calif. The project, part of the Search for Extraterrestrial Intelligence, or SETI, was suspended in April when the University of California’s Hat Creek Observatory ran out of money.

Astrobiologists have released a report outlining a number of speculative scenarios where Extraterrestrials might contact Earth, including the possibility that they may detect our global warming problems and view as us a potential resource threat.

A new survey is under way to search for signs of intelligent extraterrestrial life, but this one has a twist: Instead of listening for alien signals from anywhere in the sky, scientists are aiming radio telescopes at the alien planets most likely to be like our own Earth

The SETI Institute is launching a private beta test beginning today of SetiQuest Explorer in the hopes that hobby astronomers will help with pattern recognition tasks that can't be done well by computers. "We want to tap into the brain power of the world," Jill Tarter, director of the non-profit SETI Institute, said in an interview in her office this week.

Roughly one out of every 37 to one out of every 70 sunlike stars in the sky might harbor an alien Earth, a new study reveals. These findings hint that billions of Earthlike planets might exist in our galaxy, researchers added.

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.

When considering the prospect of alien life, humankind should prepare for the worst, according to a new study: Either we're alone, or any aliens out there are acquisitive and resource-hungry, just like us.

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.