Such a planet would lie within the habitable zone of Proxima Centauri, about 0.023–0.054 AU (3.4–8.1 million km) from the star, and would have an orbital period of 3.6–14 days.
A planet orbiting within this zone may experience tidal locking to the star.
If Proxima was bound to the Alpha Centauri system during its formation, the stars are likely to share the same elemental composition.
Moreover, the equilibrium temperature of Proxima b is estimated to be within the range where water could exist as liquid on its surface; thus, placing it within the habitable zone of Proxima Centauri.
Proxima Centauri, along with Alpha Centauri A and B, was among the "Tier 1" target stars for NASA's now-canceled Space Interferometry Mission (SIM), which would theoretically have been able to detect planets as small as three Earth masses ( Prior to the discovery of Proxima Centauri b, the TV documentary Alien Worlds hypothesized that a life-sustaining planet could exist in orbit around Proxima Centauri or other red dwarfs.
The space velocities of these stars are all within 10 km/s of Alpha Centauri's peculiar motion.
Thus, they may form a moving group of stars, which would indicate a common point of origin, Several attempts to detect a transit of this planet across the face of Proxima Centauri have been made.
Because of its low mass, the interior of the star is completely convective, causing energy to be transferred to the exterior by the physical movement of plasma rather than through radiative processes.
This convection means that the helium ash left over from the thermonuclear fusion of hydrogen does not accumulate at the core, but is instead circulated throughout the star.
A transit-like signal appearing on September 8, 2016 was tentatively identified, using the Bright Star Survey Telescope at the Zhongshan Station in Antarctica.
Proxima Centauri b is a planet orbiting the star at a distance of roughly 0.05 AU (7.5 million km) with an orbital period of approximately 11.2 Earth days.
The magnetic energy from this field is released at the surface through stellar flares that briefly increase the overall luminosity of the star.