Exoplanets & Exomoons

Two super-Earths At The Edge Of The Habitable Zone Of The Nearby M Dwarf TOI-2095

By Keith Cowing
April 21, 2023
Filed under , , , , , , , ,
Two super-Earths At The Edge Of The Habitable Zone Of The Nearby M Dwarf TOI-2095
TESS phase folded light curves after subtracting the photometric variability for TOI-2095b (top left) and TOI-2095c (top right). The best fitting model is shown in black, the circles are TESS binned data points, points are individual TESS observations. Bottom panels: residuals of the fit. — astro-ph.EP

The main scientific goal of TESS is to find planets smaller than Neptune around stars bright enough to allow further characterization studies.

Given our current instrumentation and detection biases, M dwarfs are prime targets to search for small planets that are in (or nearby) the habitable zone of their host star. Here we use photometric observations and CARMENES radial velocity measurements to validate a pair of transiting planet candidates found by TESS. The data was fitted simultaneously using a Bayesian MCMC procedure taking into account the stellar variability present in the photometric and spectroscopic time series.

We confirm the planetary origin of the two transiting candidates orbiting around TOI-2095 (TIC 235678745). The star is a nearby M dwarf (d=41.90±0.03 pc, Teff=3759±87 K, V=12.6 mag) with a stellar mass and radius of M⋆=0.44±0.02M⊙ and R⋆=0.44±0.02R⊙, respectively. The planetary system is composed of two transiting planets: TOI-2095b with an orbital period of Pb=17.66484±(7×10−5) days and TOI-2095c with Pc=28.17232±(14×10−5) days. Both planets have similar sizes with Rb=1.25±0.07R⊕ and Rc=1.33±0.08R⊕ for planet b and c, respectively.

We put upper limits on the masses of these objects with Mb<4.1M⊕ for the inner and Mc<7.4M⊕ for the outer planet (95\% confidence level). These two planets present equilibrium temperatures in the range of 300 – 350 K and are close to the inner edge of the habitable zone of their star.

F. Murgas, A. Castro-González, E. Pallé, F. J. Pozuelos, S. Millholland, O. Foo, J. Korth, E. Marfil, P. J. Amado, J. A. Caballero, J. L. Christiansen, D. R. Ciardi, K. A. Collins, M. Di Sora, A. Fukui, T. Gan, E. J. Gonzales, Th. Henning, E. Herrero, G. Isopi, J. M. Jenkins, J. Lillo-Box, N. Lodieu, R. Luque, F. Mallia, G. Morello, N. Narita, J. Orell-Miquel, H. Parviainen, M. Pérez-Torres, A. Quirrenbach, A. Reiners, I. Ribas, B. S. Safonov, S. Seager, R. P. Schwarz, A. Schweitzer, M. Schlecker, I. A. Strakhov, S. Vanaverbeke, N. Watanabe, J. N. Winn

Comments: Submitted to Astronomy & Astrophysics
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
Cite as: arXiv:2304.09220 [astro-ph.EP](or arXiv:2304.09220v1 [astro-ph.EP] for this version)
Submission history
From: Felipe Murgas
[v1] Tue, 18 Apr 2023 18:19:13 UTC (8,300 KB)

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻