Discovery




The first indications of the exoplanet were found in 2013 by Mikko Tuomi of the University of Hertfordshire from archival observation data. To confirm the possible discovery, a team of astronomers launched the Pale Red Dotnote project in January 2016. On 24 August 2016, the team of 31 scientists from all around the world, led by Guillem Anglada-Escudé of Queen Mary University of London, confirmed the existence of Proxima Centauri b through their research, published in a peer-reviewed article in Nature.

The measurements were done using two spectrographs, HARPS on the ESO 3.6 m Telescope at La Silla Observatory and UVES on the 8-metre Very Large Telescope. The peak radial velocity of the host star combined with the orbital period allowed for the minimum mass of the exoplanet to be calculated. The chance of a false positive detection is less than one in ten million.

Observational complications of the star tend to indicate additional, not insignificant size, orbiting planets. Another super-Earth was noted on discovery of this planet as possible; its presence would not destabilize the orbit of Proxima Centauri b. One very large super-Earth was discovered in 2019, known as Proxima Centauri c – it orbits at 1.5 AU away, too far to tug on the other planet at all significantly.

Data of ESPRESSO excludes extra companions with masses above 0.6 M⊕ at periods shorter than 50 days. A potential companion, Proxima Centauri d, at 0.29 M⊕, was found to have an orbit around 5.15 days. It requires further study, to confirm its existence and identify its orbital properties.

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Proxima Centauri b

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