Astronomers have already identified at least two planets orbiting our nearest stellar neighbor, Proxima Centauri. Now they can add a third to the list:
Astronomers have found evidence of a third planet around the closest star to the sun, reinforcing the idea that planets are common around the stars of the galaxy, even some of its smallest.
And while the newly-found planet is less than half the size of Earth and probably too hot to be inhabited, there's still a chance there could be life around Proxima Centauri, Earth's nearest galactic neighbor...
[Study author João] Faria, a researcher at the Institute of Astrophysics and Space Sciences at the University of Porto in Portugal, said it suggests the Proxima system could be "packed with planets."
The planet was detected using the "radial velocity technique," and this discovery has important implications for that method:
The technique works by picking up tiny wobbles in the motion of a star created by an orbiting planet's gravitational pull. The effect of Proxima d's gravity is so small that it only causes Proxima Centauri to move back and forth at around 40 centimetres per second (1.44 kilometres per hour).
"This achievement is extremely important," says Pedro Figueira, ESPRESSO instrument scientist at ESO in Chile. "It shows that the radial velocity technique has the potential to unveil a population of light planets, like our own, that are expected to be the most abundant in our galaxy and that can potentially host life as we know it."
There's nothing like a good space discovery—that out in the unfathomably cold and endless recesses of the universe, there might be something totally unexpected and mind-blowing, even if it's just the possibility of a tiny colony of bacteria on an alien planet trillions of miles away.
