By Nick Pope
This month the Royal Society held a two-day meeting to work out a “scientific and societal agenda” on extraterrestrial life, following up on a similar meeting in January. The discussions generated controversy, conspiracy theories and a little bit of acrimony. So what happened? I was there on both days, and here’s the inside story.
Scientists are searching for extraterrestrial life in a number of different ways and places. One aspect of this is the search for extrasolar planets, on the basis that an Earthlike planet around a sunlike star might be a good place to look. The first super-Earths have been discovered, and the longer-term goal will be to undertake spectral analysis of the atmospheres of such exoplanets, looking for oxygen, ozone, water and other potential indicators of life. The recent excitement over Gliese 581g brings such work into focus — though even the very existence of this world is now the matter of some debate.
Other scientists believe our best chance of discovering alien life will be a human or robotic mission in our own solar system — probably to Mars — targeted at detecting extraterrestrial microbial life. But the controversy begins with the small but vociferous group of scientists who use radio telescopes to search the sky for a signal from other civilizations.
So what happens if SETI find a signal? Do we reply? Though not present, the shadow of Professor Stephen Hawking loomed large over the meeting. Earlier this year Hawking warned bluntly that contacting aliens could have catastrophic consequences for the human race. He likened this to the arrival of Christopher Columbus in the New World, and pointed out that matters didn’t turn out too well for the Native Americans. This echoed a remark made at the Royal Society’s January conference, when Professor Simon Conway Morris, a Cambridge University palaeontologist, said “if the cosmic phone rings, don’t answer.”
Related to this question is the issue of active SETI, sometimes known as METI (messaging to extraterrestrial intelligence). This was discussed extensively at this month’s meeting, and that’s when things got heated.