On April 18, 2013, NASA’ astronomers announced the discovery of a new planetary system composed of five worlds orbiting a star somewhat cooler and smaller than the Sun, approximately 1,200 light-years away from us in the constellation Lyra.
The outermost of them, named Kepler-62f, looks hopeful for supporting life. Around 40% larger than our planet, Kepler-62f is likely a solid planet within the star’s habitable zone, where conditions may be just right for liquid water to form.
Giving its good shape and size, the unique planet may even possess surface oceans, but back then, NASA’s Kepler mission failed to gather sufficient information about Kpler-62f’ composition, atmosphere or orbit.
At that size, Kepler-62f is within the range of planets that are likely to be rocky and possibly could have oceans,
said Aomawa Shields, lead author of the study published in the May 13 issue of the journal Astrobiology.
So, to determine whether Kepler-62f could harbor life, Aomawa Shields ran computer simulations and thus came up with various scenarios of possible atmospheric conditions and orbital shape of the planet.
We found there are multiple atmospheric compositions that allow it to be warm enough to have surface liquid water. This makes it a strong candidate for a habitable planet.
On Earth, carbon dioxide makes up about 0.04% of the atmosphere. Because Kepler-62f is much farther from its parent star than Earth is to the Sun, it would need a thick carbon dioxide-rich atmosphere to stop its water from freezing — it needs to have three to five times a thicker atmosphere than the Earth’s in order to be considered consistently habitable during the entire year.
But, what if the carbon-dioxide levels are low or closer to those found on Earth? Shields estimated the temperature on the planet rises above freezing during certain times of the year which may result in melting of the ice sheets to form liquid water – enough to sustain life.
Though astronomers don’t know for sure whether life could exist on Kepler-62f, but Dr Shields is optimistic about finding life in the universe.
This technique will help us understand how likely certain planets are to be habitable over a wide range of factors, for which we don’t yet have data from telescopes,
And it will allow us to generate a prioritized list of targets to follow up on more closely with the next generation of telescopes that can look for the atmospheric fingerprints of life on another world.
Kepler-62f and Kepler’ Legacy
To date, NASA’ Kepler Telescope has discovered more than 2300 exoplanets and more than twice are as-yet unconfirmed planetary candidates, but only few are considered to belong in the “habitable zone” — the range of orbits around a star within which a planetary surface can support liquid water.
The most habitable planet to date is Kepler-452b but it is located 1,400 light-years away from us, so unless we invent a way of prolonging our lives drastically, it might remain a pipe dream for now.
But there are others relatively close planets to us that could be habitable, like Gliese 581d which is just 20 light years away; who knows, maybe soon we could detect exoplanets even closer than Gliese 581d, maybe there’s a planet in Alpha Centauri star system waiting for us to be discovered, or within the range of 10 ly from us.
Whether or not intelligent life actually exists in our universe, we know for sure there is life out there and we are getting closer and closer to find it.