ONLY 39 light-years away, astronomers have found seven planets circling a very small "red dwarf" star called Trappist-1. All seven are in or near what we call the "Goldilocks zone": not too hot, not too cold, but just right for water to remain liquid on the planet. So we all speculate once again, but a little more bravely this time, about whether some of these planets might be home to life.
Not only are three of Trappist-1's planets dead centre in the Goldilocks zone; the other four are on the fringes of the habitable zone. And they are all big enough -- from half Earth's size to slightly bigger than our home planet -- to retain an atmosphere for billions of years.
If an intelligent life form evolved on even one of these planets, it could have colonised all seven: they are very close together. The journey would be not much more demanding than a trip from the Earth to the Moon.
So think about that: a seven-world interplanetary civilisation. It may not exist at Trappist-1: we cannot yet assume that life crops up everywhere that the circumstances are suitable for it. But it surely must exist in one or many (or most) of the hundreds of millions of similar star systems that exist in this galaxy alone.
It looks like life is as common as dirt in the universe, which for living creatures like us is infinitely more interesting than a dead universe ruled only by physics and chemistry. Whereas the poor scientists, shackled by their duty to go not one millimetre further than the evidence will currently support, are condemned to say cool, restrained things like: "The discovery of multiple rocky planets with surface temperatures that allow for liquid water make this amazing system an exciting future target in the search for life." (Dr Chris Copperwheat of Liverpool John Moores University, which provided one of the telescopes used in the study.)
