We all know that Earth is particularly special within our solar system, because it is the only planet that can support life, or at least what our current definition of “life” means. One of the best hopes for finding life elsewhere in our solar system is underneath the miles of ice on the surface of Europa; however, Europa is a moon, so it still leaves Earth as the only hospitable planet.
But Earth can’t be the only planet in the billions and billions of planets scattered throughout the universe that can support life, or even intelligent life, right? In March of 2009, NASA set off to find the answer to that question with the Kepler Mission. The goal – to possibly find other planets capable of sustaining life.
One of the first things they look at is the size of a planet. They focus on Earth-sized planets, because they tend to have an abundance of rock or solid surfaces, a metal core, smaller orbits around their star, and most of the elements that we know are needed to sustain “life.” In the Milky Way galaxy alone they have determined that there are at least 40 billion earth-sized planets.
Next they want to determine if the planet is within the Circumstellar Habitable Zone, or “Goldilocks Zone.” This just means that the planet cannot be too close, or too far away from its star. The Keplar Mission has confirmed 1,004 planets that meet both the Earth-sized and Goldilocks Zone requirements.
When it began most, if not all, of the scientists didn’t expected to discover so many potential planets in such a short period of time. Not only has it shown us how abundant these planets truly are, but it has also augmented the realization that the possibility of “life” outside of Earth, could be a mathematical certainty.
All of the planets that have been located are, at the closest, hundreds of light-years away from Earth; so it will be some time before humans ever visit. But we know they are there. We just don’t know what we’ll find when we get there…
New York Times
Stuff You Should Know