It was discovered in August 2014,[3] deduced from analysis of the radial velocities of the parent star by the Eta-Earth Survey using HIRES at Keck Observatory. It has around 5.35 ± 0.75 Earth masses,[3] and is thought to be a Super-Earth with a diameter greater than that of the Earth. However, researches using the CARMENES spectrograph failed to detect the planet in 2017.[4] The detection of planet was recovered in 2018, with revised minimum mass of 3.03 ME.[1]
Gliese 15 Ab has a close inner orbit around Gliese 15 A with a semi-major axis of only 0.0717 ± 0.0034 AU, making an orbital period that is just a little longer than 11.4 days, the orbit appears to be relatively circular, with an orbital eccentricity of about 0.12. It orbits too close to Gliese 15 A to be located in the habitable zone and is unlikely to harbour life.
Notes
^In the discovery paper, discoverers call this object "Gl 15 Ab", and never "Groombridge 34 Ab".
References
^ abPinamonti, M.; Damasso, M.; Marzari, F.; Sozzetti, A.; Desidera, S.; Maldonado, J.; Scandariato, G.; Affer, L.; Lanza, A. F.; Bignamini, A.; Bonomo, A. S.; Borsa, F.; Claudi, R.; Cosentino, R.; Giacobbe, P.; González-Álvarez, E.; González Hernández, J. I.; Gratton, R.; Leto, G.; Malavolta, L.; Martinez Fiorenzano, A.; Micela, G.; Molinari, E.; Pagano, I.; Pedani, M.; Perger, M.; Piotto, G.; Rebolo, R.; Ribas, I.; et al. (2018). "The HADES RV Programme with HARPS-N at TNG. VIII. GJ15A: A multiple wide planetary system sculpted by binary interaction". Astronomy and Astrophysics. 617: A104. arXiv:1804.03476. Bibcode:2018A&A...617A.104P. doi:10.1051/0004-6361/201732535. S2CID54990041.
^Trifonov, Trifon; Kürster, Martin; Zechmeister, Mathias; Tal-Or, Lev; Caballero, José A.; Quirrenbach, Andreas; Amado, Pedro J.; Ribas, Ignasi; Reiners, Ansgar; et al. (2018). "The CARMENES search for exoplanets around M dwarfs. First visual-channel radial-velocity measurements and orbital parameter updates of seven M-dwarf planetary systems". Astronomy and Astrophysics. 609. A117. arXiv:1710.01595. Bibcode:2018A&A...609A.117T. doi:10.1051/0004-6361/201731442. S2CID119340839.