A survey of billions of stars in the Milky Way could have captured signs of intelligent life — and amateur astronomers are being encouraged to search for them. Experts at the SETI Institute are developing state-of-the-art techniques to detect signatures from space that indicate the possibility of extraterrestrial life. These so-called 'technosignatures' can range from the chemical composition of a planet's atmosphere, to laser emissions and structures orbiting other stars ...