A £1bn (€1.2bn) European space telescope to be launched in 2024 raises the real prospect of finding an alien civilisation among the stars, it is claimed.
Astronomer Don Pollacco, heading a consortium of scientists involved in the Plato mission, believes such a momentous discovery could happen in the next 15 years.
Signs of pollution in an Earth-like planet's atmosphere would indicate the existence of an industrial society – and alter our world view for ever.
"There are certain things you would not expect to occur naturally, and pollution is the obvious one," said Dr Pollacco, from the University of Warwick.
"I'm talking about various kinds of metals that would not occur in that state in that atmosphere. You would have to interpret that as a sign of some kind of civilisation.
"We could do this in our lifetime; that's the most exciting thing. It would change everything. It would be amazing."
The Plato (Planetary Transits and Oscillations of stars) space telescope will prepare the way for scientists searching for alien life by locating the first genuinely Earth-like exoplanets orbiting nearby stars.
Given the enormous age and size of the universe, the chances of stumbling on an extra-terrestrial industrial society in our cosmic backyard might be slim, but Dr Pollacco insists it cannot be ruled out. "For a long time a lot of us have been driven on by that sort of idea," he said.
The European Space Agency (ESA) yesterday announced that Plato had been selected as part of its 2015-2025 Cosmic Vision programme.