Lasers could 'cloak Earth from aliens'

We should shine lasers into space if we want to hide our presence from aliens, two US-based astronomers suggest.

The beams could compensate for the dip in light the Earth creates when it passes in front of the Sun, as viewed from far-off worlds, they contend.

A number of researchers have questioned the wisdom of advertising our existence to the galaxy.

They fear that if aliens did visit us they might not be very friendly, and could introduce disease.

The analogy is Europeans arriving in the Americas in the 15th and 16th centuries. The contact wrought havoc in the health of indigenous populations.

David Kipping and Alex Teachey from Columbia University in New York say that if we are fearful of a similar outcome from an alien encounter then lasers offer a solution.

The team has calculated what would be required to cloak the Earth and published the concept in a paper in the Monthly Notices of the Royal Astronomical Society.read more on bbc link=http://www.bbc.co.uk/news/science-environment-35938886