What Else is Lurking at Proxima Centauri?
What's the closest star to Earth? Answer: Proxima Centauri, one of three stars in the Alpha Centauri star system. Proxima Centauri is a small M-dwarf star, meaning it is red in colour, and has a relatively cool stellar temperature of about 3000°K. While small, weighing in at 12% the mass of the Sun, M-dwarf stars are the most common star type in the Universe. In 2016, an international group of researchers discovered a planet orbiting Proxima Centauri that is about 1.5x larger than Earth: the closest exoplanet to Earth! In their discovery paper, the researchers also indicated there may be a second planet orbiting Proxima Centauri, but the data didn't rule out other possible causes of the signal. It looks like the group has taken a look at their data through new eyes, and, while they haven't confirmed it to be another exoplanet in Earth's backyard, they do not believe Proxima Centauri itself is the cause of the signal.