As a matter of course, and because I co-host an astronomy program on 2RPH, I consume quite a lot space- related information, some of which I actually retain. This morning I did a short recording of a piece about the SETI program, the search for extra-terrestrial intelligence. This usually occurs by means of scanning for radio signals, finding potentially habitable exoplanets and looking for things like atmospheric biosignatures.

If you didn't already know, there are significant resources (though still insufficient) devoted to the active study of exoplanets and the wider SETI program. Thus far we have but one distinctly unusual signal (the WOW signal) received by a radio telescope 30 years ago and never repeated. Its provenance is disputed. But we have found dozens of potentially habitable exoplanets (planets outside our solar system) and as technology improves, so will our ability to look more closely at the data available.

SETI is relatively benign since we are largely sitting back, collecting and then analysing the data as it comes in. Its twin sibling, METI, is less so, for the M stands for messaging. METI actively seeks to contact ET (should any exist) through the sending of powerful messages broadcast through radio telescopes. The hope is that something intelligent and technological will be able to pick up the signal, decode it and return the favour. It is a needle in a haystack really and its unlikely to bear fruit, but suppose it does. 

Blasting out Earth's location as well as information about lifeforms and technology might seem like a fun thing to do, but suppose an intelligent advanced civilisation does receive the message? And suppose that they are bent on domination or the extermination of others to ensure their own survival. Sure, they are light years away and its takes a long time to travel in interstellar space. But it does present a danger and I am not sure who is assessing the risks.