Motions of Proxima Centauri due to Orbiting Planet

Proximab_motion.jpg

Proximab_motion.jpg

This plot shows how the motion of Proxima Centauri toward and away from Earth is changing with time over the first half of 2016. Sometimes Proxima Centauri is approaching Earth at about 3 miles per hour (5 kph) — normal human walking pace — and at times receding at the same speed. This regular pattern of changing radial velocities repeats with a period of 11.2 days. This indicated the presence of a planet with a mass at least 1.3 times Earth's, orbiting about 4.4 million miles (7 million km) from Proxima Centauri — only 5% of the Earth-Sun distance. Credit: ESO/G. Anglada-Escudé