Free Astronomy Magazine July-August 2020

JULY-AUGUST 2020 first half of 2016, the HARPS spectrograph, installed on the ESO’s 3.6-meter telescope (La Silla Observatory, Chile), was used for a total of 60 nights to show the researchers more clearly than before that Proxima Cen- tauri cyclically approaches and moves away from the Earth at a speed of about 1.4 m/s over a period of 11.2 days. The possibility that this behavior was attributable to the magnetic activity of the star (the expansion and contraction movements of the photos- phere) was ruled out. The most convincing interpretation of the phenomenon was the presence of a planet that, traveling in its orbit, attracted the star towards itself. The 11.2-day period would then be the time it takes for the planet to orbit the star, from which a planet-star distance of just 0.05 AU was calculated, equal to one-twentieth that of the Earth-Sun distance. If the orbital planes of our Solar System and Proxima Centauri were aligned just right, we would be able to observe the transits of a planet from Earth, when the planet passed directly in front of Proxima Centauri’s stellar