How to talk to ET

At the Astrobiology Science Conference 2010 in April, scientists working on the Search for Extraterrestrial Intelligence (SETI) will debate whether it's a good idea to systematically start transmitting interstellar greetings into space. Of course, there have been isolated efforts to reach out to our space brothers before. For example, SETI pioneer Frank Drake created the 210 byte message seen here and transmitted it from the Arecibo telescope in 1974. It's not expected to reach its detination, the star cluster M13, for another 25,000 years though. Can we come up with communications that might be easier for an ET to grok, perhaps also using mathematics and pictures? And even if we can, should we? From New Scientist:

(SETI Institute's head of the Interstellar Message Composition program Douglas) Vakoch, who will chair these sessions, is all in favour. "I have long held the position that after broad-based international consultation, we should be doing active SETI," he says.

It's an approach that worries ex-astronomer and science fiction author David Brin, who was a member of the International Academy of Astronautics SETI panel until 2006. He resigned when the committee backtracked on the wording of a protocol that called for discussion before deliberately broadcasting into space. "I dislike seeing my children's destiny being gambled with by a couple of dozen arrogant people who cling to one image of the alien," says Brin. Since then three other members have quit for similar reasons. Vakoch has some sympathy with Brin's point of view. "These issues are much too important and too complex to be resolved after only a few days of discussion."

If the enthusiasts for active SETI get their way and there is a real effort to send a message, the next question is: what should we say?…

"Redundancy really helps," says Shostak, as it allows a recipient to make a guess about the meaning and then check it, like in a crossword. He suspects that all the polite efforts to be understood might be unnecessary. "A lot of people wonder what we should send. Music, mathematics or pictures? My first thought is it probably doesn't matter," he says.

Instead, (SETI Institute senior astronomer Seth) Shostak suggests that we just gabble. "My conclusion is that you would just send them the Google servers. That's an enormous amount of information, much of it redundant and pictographic. Much of it is pornographic too, but I expect they could handle that." (Although it raises questions like, can Earth handle a trillion orders for Viagra?)