EARTH is probably a youngster among planets of its kind, says an astronomer
in Australia. This may mean that any intelligent beings that have evolved on
other Earth-like planets will be so highly advanced that to them we seem little
better than bacteria. No wonder they haven’t been in touch yet.
Charles Lineweaver of the University of New South Wales in Sydney says that
Earth-like planets orbiting other stars will be on average about 1.8 billion
years older than Earth. He deduced this figure by cleverly combining a host of
factors that determine the formation and destruction of terrestrial planets.…
