An exoplanet in the Solar System’s vicinity may host life, astronomers bet.

Discovered in August 2016, Proxima Centauri b, a rocky planet in the Proxima Centauri System 4.2 light-years from Earth, has been fascinating astronomers and scientists looking for extraterrestrial life. 

Due to the fact that it circles the host star, a red dwarf that gave the system its name, in the so-called habitable zone, there are chances that it has a vast ocean of liquid water on its surface and the planet therefore may be able to support life.

A study based on simulations show that under the right conditions there are “decent chances” the planet which is 1.3 times the mass of Earth is habitable. 

An artist impression of Proxima b's landscape. Credit: Wikipedia

Proxima b orbits the star, which is cooler but the same age as the Sun, at about 7.5 million kilometers over a period of 11.2 Earth days.

The planet and the star are tidally locked, which means Proxima b “looks” at Proxima Centauri with the same side and any water on the dark side would be in frozen state but on the other side it would be dynamic.

More to read:
Saturn moon squirted an enormous water vapor into space

In the study, the researchers ran the first climate simulations of Proxima b with a dynamic ocean.

“Climate models with static oceans suggest that Proxima b could harbor a small dayside surface ocean despite its weak instellation. With a dynamic (moving) ocean considered for the first time, the extent of this liquid water becomes much more significant, in some cases even dipping into parts of the nightside. The simulations showed that ‘with a dynamic ocean, a hypothetical ocean-covered Proxima Centauri b with an atmosphere similar to modern Earth’s can have a habitable climate with a broad region of open ocean, extending to the nightside at low latitudes,” the researchers explained.

They used different models of salinity levels and atmospheric greenhouse gas concentrations to determine the size of the liquid regions. In more than a dozen simulations, the researchers found that the planet almost always had some sort of liquid ocean.

“We find that an ocean-covered Proxima b could have a much broader area of surface liquid water but at much colder temperatures than previously suggested, due to ocean heat transport and/or depression of the freezing point by salinity,” the researchers wrote.

Earlier studies had suggested that only a small region between the dark side and the light side could attain liquid water.

Proxima Centauri is part of a multiple star system, whose other members are Alpha Centauri A and Alpha Centauri B which form a binary star subsystem. The equilibrium temperature on Proxima b is estimated at minus 39 degrees Celsius.