Tap to Read ➤

6 Facts About Alien Planet 'Kepler-186f' Worth Knowing

Satyajeet Vispute Oct 13, 2020
The discovery of the alien planet Kepler-186f could very well be a landmark achievement of modern-day astronomy. In the scientific community, it is being called Earth's cousin. Curious to know why? Then read on to discover some more amazing facts about this distant yet alluring exoplanet.

An Everlasting Sun

The Kepler-186 is an M1 dwarf star. These stars are known to burn hydrogen forever, and so, there would be enough time and opportunities for life to develop on Kepler-186f which orbits it.
There are billions of stars in the Milky Way alone, and yet, we know of only one that shines over life as we know to exist. But are we alone? Is the Earth unique or are there other solar systems like ours out there in the Universe?
Now, scientists may be able to answer these questions, thanks to the most powerful planet hunter ever built―the Kepler space telescope.

Since it began operating, Kepler has been making astonishing discoveries. It has shown us that there are in fact a huge number of planets out there.
They range from enormous gas giants to miniature rock and iron dwarfs. It has discovered lands where the Sun never sets and others where there two Suns similar to the home planet of Luke Skywalker. But what we are really interested in finding is an Earth analog, a planet capable of sustaining life.
Of the 1013, and counting, confirmed planets discovered by Kepler, only a few fit this criterion. The first one to be discovered among these was the Kepler-186f, which has been nicknamed 'Earth's Cousin'. The following are the main facts about this Earth-like exoplanet.

Facts About Alien Planet 'Kepler-186f

When Was Kepler-186f Discovered

The historic discovery of the Earth-like exoplanet Kepler-186f was publicly announced by NASA on April 17, 2014. Prior to that, initial results and findings had been submitted at a conference on March 19, 2014, and some of the details had been provided to the media.
Scientists collated and analyzed nearly three years of data collected by Kepler space telescope to confirm the planet's signal and its existence.

How Did They Find Kepler-186f

Kepler-186f was found by the Kepler telescope using the innovative detection technique known as transit photometry. The following describes the working of this technique.
Planets themselves are non-luminous, hence, instead of directly looking for them, the Kepler space telescope focuses on their parent stars, measuring their brightness. When a planet orbiting its star transits or crosses in front of it, the brightness of the star, as perceived by Kepler, dims by a small amount.
This amount depends on the star's radius relative to that of the planet orbiting it. Hence, along with confirming a planet's existence and location, Kepler is also able to calculate its size. Along with this, it can measure the orbit-time duration of the planet by measuring the time difference between two consecutive dims.
In case of the Kepler-186f, the transit photometry technique was employed for nearly three years and that allowed NASA to discover and confirm its existence.

Where is Kepler-186f Located?

Kepler-186 is a M1 dwarf star located in the constellation Cygnus, nearly 500 light years away from Earth. It is about half as massive as our Sun and is therefore, much cooler. This star has five planets orbiting around it.
They are Kepler-186b, Kepler-186c, Kepler-186d, Kepler-186e and Kepler -186f. Among these, only Kepler-186f is in the center of habitable zone, while the rest have short orbits and are very hot.
The habitable zone is the orbital region which is present at the right distance away from a star to allow liquid water to pool on a planet's surface. If a planet is closer to the star than this region, it will be too hot and the water in it would evaporate.
If it is beyond this region, the planet would be too cold and water in it would freeze. Kepler-186f is on the outer edge of the habitable region.

Kepler-186f Characteristics

Kepler-186f has a radius that is about 1.1 times (10%) that of Earth. Its orbital radius is about 37 million miles or 0.40 times that of Earth, and it is believed to orbit its star once after every 130 days. Kepler-186f is most likely a rocky planet similar to Earth or Mars, though the land mass in it might very well be completely submerged under water.
Its parent star Kepler-186 being an M1-dwarf, shines with a luminosity that is only about 4% that of the Sun. Astronomers have estimated that this planet receives about one-third the heat energy that we receive from the Sun.

Does Kepler-186f Have an Atmosphere?

Kepler-186f is too distant for us to analyze its atmospheric characteristics using existing telescopes.
One climatic model, in which the atmospheric composition is restricted to only nitrogen, carbon dioxide, water vapor and clouds are not considered, suggests that the temperature on Kepler-186f would be above 273ºK (0ºC). This would cause the water on the planet to freeze.
The larger size of the planet, however, could mean that it has a thicker atmosphere. If it does and it comprises enough carbon dioxide, it could act as an insulator preventing the heat from escaping from the surface of the planet. This could raise its temperature.

Is there Life on Kepler-186f

The discovery of Kepler-186f is of great significance as it is the first discovered exoplanet that is nearly equivalent in size to Earth and is present on the fringes of what is known as the 'habitable zone'.
This makes it likely that the Kepler-186f has liquid water on its surface, which, according to our current knowledge, is a prerequisite for the existence of life.
Kepler-186f might also possess a favorable atmosphere. Its size suggests that it must be a rocky planet like Earth or Mars, and the gravity on it must only be slightly higher than that on Earth. All these conditions are appropriate for life to exist.
Hence, it wouldn't be too far fetched to consider the possibility of the presence of life on this planet. However, development of life depends on a very delicate balance between a number of parameters. So until we can actually analyze this planet up close, it would be best not to jump to any conclusions.
The discovery of Kepler-186f has reaffirmed the possibility that we might not be alone in the Universe after all. It is a planet that is very similar to our Earth and considering all its characteristics, it could possibly harbor alien life.
The frontiers of science have allowed us to locate it and might even make it possible for us to reach it in the future. The Kepler-186f might one day become our home away from home.