A plan by NASA to beam the Earth's location into outer space could spark an alien invasion.
Scientists are hoping to send details about our planet to the part of the Milky Way that is most likely to have extra-terrestrials.
The Beacon In The Galaxy message will end with an invitation for alien civilisations to respond but some fear that it could be a disastrous move.
Toby Ord, from Oxford's Future of Humanity Institute, has warned that the message could alert hostile aliens that Earth will welcome them.
He said: "This doesn't sound like a good situation in which to take active steps toward contact."
The broadcast will include information about the solar system's location as well as digital depictions of the Earth's surfaces and male and female humans.
The beacon was devised by Jonathan Jiang, from NASA's Jet Propulsion Laboratory, and his team thinks aliens are intelligent enough to "know the importance of peace and collaboration".