an Earth around the Nearest Star
University of Geneva | 2020 May 28
Researchers from the University of Geneva, have confirmed the existence of the Proxima b extrasolar planet using measurements from the Swiss-built ESPRESSO spectrograph.
The existence of a planet the size of Earth around the closest star in the solar system, Proxima Centauri, has been confirmed by an international team of scientists ... The results ... reveal that the planet in question, Proxima b, has a mass of 1.17 earth masses and is located in the habitable zone of its star, which it orbits in 11.2 days. This breakthrough has been possible thanks to radial velocity measurements of unprecedented precision using ESPRESSO, the Swiss-manufactured spectrograph – the most accurate currently in operation – which is installed on the Very Large Telescope in Chile. Proxima b was first detected four years ago by means of an older spectrograph, HARPS – also developed by the Geneva-based team – which measured a low disturbance in the star’s speed, suggesting the presence of a companion.
The ESPRESSO spectrograph has performed radial velocity measurements on the star Proxima Centauri, which is only 4.2 light-years from the Sun, with an accuracy of 30 centimetres a second (cm/s) or about three times more precise than that obtained with HARPS, the same type of instrument but from the previous generation. ...
Revisiting Proxima with ESPRESSO ~ A. Suárez Mascareño et al
- Astronomy & Astrophysics (accepted 11 May 2020) DOI: 10.1051/0004-6361/202037745
- arXiv.org > astro-ph > arXiv:2005.12114 > 25 May 2020 (v1), 26 May 2020 (v2)