Klaatu barada nikto …

… Aliens in the age of anxiety. (Hat tip, Dave Lull.)

But what are we actually looking for? Fellowship in what the 17th-century French mathematician Blaise Pascal called “the eternal silence of these infinite spaces”? We may not find it; there is no reason to think that aliens would be anything like us. Martin Rees, the Astronomer Royal, suspects that organically based intelligence may be a “brief interlude before the machines take over”. So, on a planet orbiting a star much older than our own, we may only find non-biological entities. Or we may not find them there at all; they may have emigrated to space to escape the kind of planetary crises we are now confronting. Rees argues that we would be staggeringly lucky to “catch intelligence” in the brief moment in which it was embodied in flesh and blood.