What is it about life outside the Earth that excites us so much? This was one of the questions Ian Sample of The Guardian asked Dr Stuart Clark two weeks back on the Science Weekly podcast. Around nineteen minutes into the show comes the question, “Why are we so keen on this idea?… There is something about this which seems to be endlessly appealing to us. What is this?”
“I thought about this a lot,” replies Dr Clark, “because I wanted to imbue (the book) with some sense of the philosophy of why we do this and why this seems to capture us so much.” He is, of course, talking about his latest book, The search for Earth’s twin. I think he comes up with a rather diplomatic answer: the idea that there could be other planets with life out there, he says, is “terrifically life-affirming”. To astronomers and astrophysicists, and to physicists in general, this is a question less about faith and more about the work we do. On the one hand is how Mr Sample points out that articles written about Earth-like planets become wildly popular on the web irrespective of how many remarkably similar ones get published in even a brief span of time, which is strangely true, and how Dr Clark attributes it to human nature, which is also true, and on the other is a harder truth: the Earth will not last forever, humans want to.
What makes a planet Earth-like?
The search for other planets is a recent one, starting around 1995, and it was accelerated some years ago with the launch of NASA’s Kepler mission which led to the discovery of thousands of planets. Continue reading