Long odds of finding ET

The odds of successfully eavesdropping on the daily radio traffic of extraterrestrial life forms have been calculated by a pair of UK scientists to be astronomically small.

The calculation is presented in a paper accepted for publication in the International Journal of Astrobiology and appearing on the pre-press website arXiv.org.

Duncan Forgan, from the University of Edinburgh and Professor Bob Nichol from the Institute of Cosmology and Gravitation, used a computer modelling technique, called Monte Carlo Realisation, to simulate the growth and evolution of intelligent life in our galaxy.

They combined this with previous research showing the next-generation Square Kilometre Array (SKA) telescope will be able to pick up radio traffic from ET up to distances of 300 light years from Earth.

They calculated that the probability of picking up such transmissions as being extremely low - 1 in 10 million, to be precise.

Forgan and Nichol assume that ET will only "leak" radio signals for about 100 years of its civilisation.

They say humans have been leaking signals from TV and military radar for that length of time, but are now becoming "radio quiet" as signals move to lower power.