University of Hertfordshire

A low-mass planet candidate orbiting Proxima Centauri at a distance of 1.5 AU

Research output: Contribution to journalArticle


  • M. Damasso
  • Fabio Del Sordo
  • Guillem Anglada Escude
  • P. Giacobbe
  • Alessandro Sozzetti
  • L. Morbidelli
  • G. Pojmański
  • Domenico Barbato
  • R. P. Butler
  • Franz-Josef Hambsch
  • James S. Jenkins
  • Maria J. Lopez-Gonzalez
  • Nicolas Morales
  • Pablo A. Peña Rojas
  • Cristina Rodriguez-Lopez
  • Eloy Rodriguez
  • Pedro J. Amado
  • Guillem Anglada
  • F. Feng
  • Jose F. Gómez
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Original languageEnglish
Article numbereaax7467
Number of pages14
JournalScience Advances
Publication statusPublished - 15 Jan 2020


Our nearest neighbor, Proxima Centauri, hosts a temperate terrestrial planet. We detected in radial velocities evidence of a possible second planet with minimum mass m c sin i c = 5.8 ± 1.9 M ⊕ and orbital period P c = 5.21 - 0.22 + 0.26 years. The analysis of photometric data and spectro-scopic activity diagnostics does not explain the signal in terms of a stellar activity cycle, but follow-up is required in the coming years for confirming its planetary origin. We show that the existence of the planet can be ascertained, and its true mass can be determined with high accuracy, by combining Gaia astrometry and radial velocities. Proxima c could become a prime target for follow-up and characterization with next-generation direct imaging instrumentation due to the large maximum angular separation of ~1 arc second from the parent star. The candidate planet represents a challenge for the models of super-Earth formation and evolution.


Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).

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