Our next story seems to have the science world abuzz today. A new paper was published in Nature Communications that examines the progress made in observational methods that allow us to hunt for potentially habitable planets. The first system they looked at with this new method was Alpha Centauri, which is the closest star system to our own at only 4.3 light-years away.
And they possibly have found a planet in the habitable zone.
Alpha Centauri is a triple star system with two stars, A and B, orbiting each other as a binary system. They are about the size and age of our own Sun. A third star, commonly known as Proxima Centauri, orbits the binary pair but much farther out. These new observations focused on the inner binary, and here’s how the method works, as explained by the press release:
By moving one star on the coronagraph and one star off the coronagraph every tenth of a second, this technique has allowed researchers to observe each star for half the time, and more importantly it has allowed them to subtract one image from the next, which removes all but the noise of the camera and telescope. After removing the known artefacts created by the instrumentation and the residual light from the coronagraph, the final image revealed a light source designated as “C1”, a plausible detection, which could be a planet the size of Neptune to Saturn, located at a distance from Alpha Centauri A similar to that between the Earth and the Sun.
Whew. So. There’s a possible planet in the habitable zone of Alpha Centauri, and we can directly image it. Possibly. Maybe. The team plans to do a second observing campaign and use other methods like radial velocity measurements to confirm this discovery. We’ll update you here on the Daily Space when that happens.
University of Liège press release
University of Arizona press release
“Imaging low-mass planets within the habitable zone of α Centauri,” K. Wagner, A. Boehle, and T. de Zeeuw, 2021 February 10, Nature Communications