Alien life might already live among us / Samantha Rolfe -- Aliens may have already visited / Jasper Hamill -- Advanced civilizations have probably developed previously elsewhere in the universe / Lenor Sierra -- Most likely number of contactable alien civilisations is 36 / Nicola Davis -- The aliens we're looking for may already be dead / Tom Siegfried.

The ingredients for earthly life appear to be almost everywhere we've looked / Pat Brennan -- We might not recognize alien life even if it's right under our feet / Samantha Rolfe -- Aliens may have already visited / Jasper Hamill -- The most likely number of contactable alien civilization is 36 / Nicola Davis -- We're probably alone / Matt Williams -- Aliens may already be out there, but scientists are waiting for better evidence / Chris Impey -- Extraordinary claims from experienced scientists are disliked by the scientific community / Simon Goodwin -- The UFO craze may be a problem of intelligence failings / Kyle Cunliffe -- The Office of the Director of National Intelligence's preliminary assessment on unidentified aerial phenomena / Office of the Director of National Intelligence -- If they're out there, they already know about us / Sean Webby -- If aliens are watching us, they may not like what they see / Michael P. Oman-Reagan -- Trying to hide from aliens would do more harm than good / Seth Shostak -- For safety's sake, we should bring quantum science to the search for ET / Matt Williams -- What will we do if we actually make contact? / Fraser Cain -- Private money makes the search for ET a better bargain / Daniel Clery -- SETI-style searches are a waste of time and money / Andrew Norton -- The new era of space exploration is only concerned with commercialization / Victor L. Shammas and Tomas B. Holen -- Looking for aliens is good for society (even if there aren't any) / Ian Crawford.