We're Not Alone: Astronomers Estimate There Are 10 Billion Planets Like Earth

Astronomers using the European Southern Observatory’s HARPS telescope have studied over 100 nearby red dwarf stars over the last six years. 40 percent of these common stars were observed to wobble, a reaction caused by the gravitational pull of an orbiting planet. 

Based on this small sample, the astronomers crunched the numbers, and extrapolated the results to cover our entire Galaxy. In other words, instead of guessing, we can calculate that there are 10 billion potentially habitable planets in our Galaxy. 

What are the characteristics of an Earth-like planet? They need to be in the so-called Goldilocks zone, which means they are neither too hot nor too cold to have liquid water which is necessary to support life as we know it. 

Now let's consider life as we barely know it -- life that exists in the most extreme environments that exist on Earth such as where James Cameron has visited in his DeepSea Challenger. Or consider a type of bacteria that can live inside a nuclear reactor. 

These are the types of life forms that Bill Nye, who heads The Planetary Society, calls "extremophile." In other words, these creatures like to live under extreme conditions (and would probably think humans are weird, Nye says). Nye told Big Think in a recent interview that if extremophiles are ubiquitous in our Galaxy, the possibility of life on another planet grows higher and higher.

Watch the video here:

Editor's note: Nye's latest effort called "Consider The Following" is a series of short videos in support of the ExploraVision Awards that are designed to get young people "excited about science so that we will have more scientists and especially engineers in the future so that we can—dare I say it—change the world."  

Image courtesy of Shutterstock

Follow Daniel Honan on Twitter @Daniel Honan

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