Planet Found in Habitable Zone Around Nearest Star to Earth
Posted on August 24, 2016
Astronomers have found a planet, Proxima b, with a mass similar to that of Earth in the habitable zone around Proxima Centauri. Proxima Centauri is the nearest star to Earth after our Sun. It is just over four light-years from our Solar System. It is a faint star in the constellation of Centaurus that is too faint to be seen with the naked eye.
An artist's impression of Proxima b its surface are pictured. The planet was discovered by researchers from the Pale Red Dot campaign. The research team was led by Guillem Anglada-Escude, from Queen Mary University of London.
Anglada-Escude says in a statement, "The first hints of a possible planet were spotted back in 2013, but the detection was not convincing. Since then we have worked hard to get further observations off the ground with help from ESO and others. The recent Pale Red Dot campaign has been about two years in the planning."
Proxima b is a 1.3 Earth mass planet. It orbits much closer to its star than Mercury does to the Sun but the star itself is far fainter than the Sun. It completes its orbital period in just 11.2 days. This enables it to be in the habitable zone of its star with a surface temperature that would allow for liquid water.
The surface of Proxima b is expected to subject to ultraviolet and X-ray flares that are far more intense than on Earth. One of the researchers says the planet receives 60 times more high-energy radiation than the Earth.
Anglada-Escude also says, "Many exoplanets have been found and many more will be found, but searching for the closest potential Earth-analogue and succeeding has been the experience of a lifetime for all of us. Many people's stories and efforts have converged on this discovery. The result is also a tribute to all of them. The search for life on Proxima b comes next..."
A research paper on the discovery can be found here in Nature.