Somewhere around 4.5 billion years ago a gigantic ball of mass started to take shape and would eventually become where we all live. So, the notion of a planet that can harbor life is not a strange one - after all, we happen to live on one. Are there any other places that are similar? Can we live on another planet?
For the past 200,000 years or so humanity has been here on Earth. In that time we've figured out how to use fire, harvest crops, change water streams, develop communities, embrace technology and learn about what happens beyond our tiny little cosmic stage. Not bad for a new species! Regardless, one thing we have yet to do is gain tactile proof of life existing anywhere else in the universe.
In order to search for life in other parts of the universe one needs to have a basic set of requirements. For example, the functionality of everything we know here on Earth can be traced back to our sun, so to look for other similar situations we must look at other stars (suns). Well, we also know that the Earth is both rocky and has water. Those are two more qualifications needed to search for similar conditions. There's also the matter of temperature. For example, Mercury is very hot, too hot to hold any life as we know it. Similarly the moons of Pluto are far too cold for our taste. Thus the position of the planet relative to its host star is a big deal as well.
Also, keep in mind, looking for planets is no easy task, the stars they orbit are so far away that we only see them as little dots of light in the night sky. Scientists have tried various methods such as the wobble or transit methods to hone in on and fine tune their understanding of such faint and distant worlds. However, this incredibly complicated process has shown some remarkable data. For example, in recent years we've gathered enough data to say that there's a really good chance that planets outnumber the stars in our universe. NASA's official exoplanet list grows all the time and we're up to over 8.8 billion potentially trip-worthy planets in our Milky Way galaxy alone. Regardless, it takes a lot of factors in just the right balance to allow for comparable conditions to our home here on Earth.
Our Earth is a good size, one that can use its gravitational pull to keep our atmosphere. Aside from that, our distance from the sun allows for tolerable temperatures and the existence of liquid water. Those two are very important aspects of planet-hunting. As of now we're the only place in the known universe to be this size and this distance from our host star. Well, we were the only place...
Recently, scientists used data from the Kepler Space Telescope and announced the first ever exoplanet discovered to be a similar size and a safe relative distance from their host star. Kepler 186f is one of 5 planets that orbits its red dwarf star. How far is it? About 500 light years from here - bring a book, it's a long trip.
So, we may not be able to go visit this place anytime soon, but this discovery is very important as it highlights the possibility of another life-harboring situation out there. It has taken us around 200,000 years to get from the first time we opened our eyes to today where we can learn about the vast distant reaches of the cosmos. The work that lays ahead for future generations could yield some remarkable findings on our universe, its creation and perhaps even a better understanding of who or what we are in the grand scheme of things.
Kepler 186f now joins the billions of other exoplanets discovered, but stands out with the distinction that it's the first exoplanet that meets a lot of the special qualifications needed to hold the most mysterious part of our universe, life.