Free Astronomy Magazine September-October 2016

5 SEPTEMBER-OCTOBER 2016 SPACE CHRONICLES the world. Guillem Anglada-Escudé explains the background to this unique search: “The first hints of a possible planet were spotted back in 2013, but the detection was not convincing. Since then we have worked hard to get further observa- tions off the ground with help from ESO and others. The recent Pale Red Dot campaign has been about two years in the planning.” The Pale Red Dot data, when com- bined with earlier observations made at ESO observatories and else- where, revealed the clear signal of a truly exciting result. At times Prox- ima Centauri is approaching Earth at about 5 kilometres per hour — nor- mal human walking pace — and at times receding at the same speed. This regular pattern of changing ra- dial velocities repeats with a period ound Proxima Centauri T his artist’s impression shows a view of the surface of the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to the Solar System. The double star Alpha Centauri AB also appears in the image to the upper-right of Proxima itself. Proxima b is a little more massive than the Earth and orbits in the habitable zone around Proxima Centauri, where the tempera- ture is suitable for liquid water to exist on its surface. [ESO/M. Kornmesser]