The Proxima Cen Exoplanetary System
Proxima Cen is a star with 0.12 times the mass of the Sun, and 0.14 times its radius. It is located 4.24 light years away from the solar system.
Proxima Cen is known to have 1 exoplanets in orbit around it.
Proxima Cen b
Proxima Cen b was discovered by the European Southern Observatory observatory using the radial velocity method. Its discovery was announced in 2016-08. Its semi-major axis is 0.05 astronomical units, as compared to Earth's which is 1 astronomical unit. It takes 11.19 Earth days to complete an orbit around its host star, Proxima Cen.
Its eccentricity, the extent to which the shape of the exoplanet's orbit departs from a perfect circle (Earth's is 0.0167, which is why the shape of Earth's orbit is circular rather than oval in appearance), is 0.35, which means that when Proxima Cen b is at is at its closest point to its host star, 0.03 astronomical units separates the two, and when it is at its farthest point, this number is 0.07. In the case of Earth, these numbers are 0.9832899 and 1.0167103 respectively.
The mass of Proxima Cen b is 1.27 times the mass of Earth. At less than 1.5 Earth masses, Proxima Cen b is a regular terrestrial planet, much like the terrestrial planets we find in our solar system, namely Mercury, Venus, Earth and Mars.
With a semi-major axis of 0.0485 astronomical units, and a mass of 1.27 Earth masses, Proxima Cen b could, potentially, be a habitable planet with stable bodies of liquid water on its surface, like Earth.