Scientists at a US science conference have said it is now time to actively try to contact intelligent life on other worlds.
Researchers involved in the search for extra-terrestrial life are considering what the message from Earth should be.
The call has been made by at the American Association for the Advancement of Science meeting in San Jose.
But others argued that making our presence known might be dangerous.
Researchers at Seti have been listening for signals from outer space for more than 30 years using radio telescope facilities in the US. So far there has been no sign of ET.
The organisation’s director, Dr Seth Shostak told scientists at the AAAS meeting that it is now time to step up the search.
“Some of us at the institute are interested in ‘active Seti’, not just listening but broadcast something maybe to some nearby stars because maybe there is some chance that if you wake somebody up you’ll get a response,” he told BBC News.
The concerns are obvious, but sitting in his office at the institute in Mountain View, California, in the heart of Silicon Valley he expresses them with characteristic, impish glee.
Any society that could come here and ruin our whole day by incinerating the planet already knows we are here”
Dr Seth ShostakSeti Institute
“A lot of people are against active Seti because it is dangerous. It is like shouting in the jungle. You don’t know what is out there, you better not do it. If you incite the aliens to obliterate the planet, you wouldn’t want that on your tombstone, right?”
I couldn’t argue with that. But initially, I could scarcely believe I was having this conversation at a serious research institute rather than a science fiction convention. The sci-fi feel of our talk was underlined by the toy figures of bug-eyed aliens that cheerfully decorate the office.
But Dr Shostak is a credible and popular figure and has been invited to present his arguments at America’s largest gathering of scientists at the AAAS meeting.