Larry Klaes tackles the METI question — do we intentionally broadcast to the stars? — in Athena Andreadis’ Astrogator’s Logs today, looking at the pros and cons of an issue that continues to bedevil the scientific community. Of METI advocate Alexander Zaitsev (Russian Academy of Science), for example, Klaes writes this:

In a paper Zaitsev published in 2006, the scientist notes that “SETI is meaningless if no one feels the need to transmit.” Zaitsev also feels that if there are advanced cultures bent on harming humanity, they will find us eventually, so it is in our best interests to seek them out first. Zaitsev sees the great distances between stars and the physical limits imposed by attempting to attain light speed serve as a natural protective barrier for our species and any other potentially vulnerable beings in the galaxy.

David Brin among others takes the other side of the debate in an article tuned for newcomers to these issues. And that’s an important audience. Most scientifically literate people know that we are listening for signals from extraterrestrial civilizations, with varying thoughts on the possibilities for success. But many don’t yet realize that powerful messages have already gone out, not only the Arecibo signal of 1974, but more recent broadcasts from the Evpatoria planetary radar site in the Crimea, and NASA’s Deep Space Network facility in Spain. The more public awareness the issue can generate, the better for balanced discussion.