Simulations show planet orbiting Proxima Centauri could have liquid water

May 18, 2017 In findings published Tuesday in , a team of scientists led by Ian Boutle at the have created successful simulations of two possible atmospheres of, an exoplanet orbiting , one a simple atmosphere of nitrogen tinged with carbon dioxide and another an. They found it possible that liquid water, a prerequisite for life as we know it, might exist on parts of the planet. The University of Exeter's lead exoplanet modeller, Dr. Nathan Mayne, in remarks to , said, "If, and it is a huge if, the composition of the atmosphere was Earth-like then we showed the planet could indeed support temperatures which would allow liquid water on the surface". In another statement, he emphasized researchers could also "exploit this to hopefully improve our understanding of how our own climate has and will evolve".

Proxima B is believed roughly Earth-sized and in its solar system's, meaning it would have similar gravity to Earth and at least the possibility of liquid water. The exoplanet was discovered in August 2016 about 4.2 s from Earth. Last year, NASA put out a statement expressing doubt that the planet could have an atmosphere in the sense that most of us understand it: "Considering the host star's age and the planet's proximity to its host star, the scientists expect that Proxima B is subjected to torrents of and extreme  radiation from superflares occurring roughly every two hours."

Co-author Dr. James Manners said, "One of the main features that distinguishes this planet from Earth is that the light from its star is mostly in the near [...] These frequencies of light interact much more strongly with water vapour and carbon dioxide in the atmosphere which affects the climate that emerges in our model."

This new model allowed scientists to evaluate the effects of Proxima B's possible orbits and likely exposure to radiation and from its  sun on two types of atmospheres. The specifics of Proxima B's orbit are not yet established. It might rotate around its axis quickly the way Earth does or it might be to its sun, with one side of the planet always lit and the other always dark. It might have a near-circular orbit or an elliptical one. All these variations would have different effects on the flow of any gases over its surface. The models described in this paper review two possible orbits: one tidally locked and one modeled after Mercury's, with a slow-rotating three days per year.

The team used the  to produce the simulations.