Astronomers have discovered over 4,000 exoplanets, or planets orbiting other stars, a number that doubles every two years. Some of these exoplanets are considered habitable, since they are close to the Earth’s mass and at the right distance from their stars to have water on their surfaces. The nearest of these habitable planets are less than 20 light years away, in our cosmic “back yard.” Extrapolating from these results leads to a projection of 300 million habitable worlds in our galaxy. Each of these Earth-like planets is a potential biological experiment, and there have been billions of years since they formed for life to develop and for intelligence and technology to emerge.
Astronomers are very confident there is life beyond the Earth. As astronomer and ace exoplanet-hunter Geoff Marcy, puts it, “The universe is apparently bulging at the seams with the ingredients of biology.” There are many steps in the progression from Earths with suitable conditions for life to intelligent aliens hopping from star to star. Astronomers use the Drake Equation to estimate the number of technological alien civilizations in our galaxy. There are many uncertainties in the Drake Equation, but interpreting it in the light of recent exoplanet discoveries makes it very unlikely that we are the only, or the first, advanced civilization.
This confidence has fueled an active search for intelligent life, which has been unsuccessful so far. So researchers have recast the question “Are we alone?” to “Where are they?”
Chris Impey, “I’m an astronomer and I think aliens may be out there – but UFO sightings aren’t persuasive” at The Conversation
The reason sightings claims aren’t persuasive is that so many of the people who make them seem to need something like that to happen in their lives. It’s not like you were harvesting tonnes of potatoes in Prince Edward Island and suddenly aliens appear and want you to read their ridiculous boilerplate to the United Nations … at the height of the potato harvest.
= Oh hell. Couldn’t they at least have picked someone else?
There may or may not be other intelligent life forms out there. As it happens, we may be in a position to get hard evidence in the next century. But there is no time when it more pays to be sceptical than a time when we could get genuine information. Or not.
Note: Prince Edward Island is an island province of Canada, famous for its potato crop.