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Abstract We present the discovery of TOI 762 A b and TIC 46432937 b, two giant planets transiting M-dwarf stars. Transits of both systems were first detected from observations by the NASA TESS mission, and the transiting objects are confirmed as planets through high-precision radial velocity observations carried out with Very Large Telescope/ESPRESSO. TOI 762 A b is a warm sub-Saturn with a mass of 0.251 ± 0.042MJ, a radius of 0.744 ± 0.017RJ, and an orbital period of 3.4717 days. It transits a mid-M-dwarf star with a mass of 0.442 ± 0.025M☉and a radius of 0.4250 ± 0.0091R☉. The star TOI 762 A has a resolved binary star companion, TOI 762 B, that is separated from TOI 762 A by 3.″2 (∼319 au) and has an estimated mass of 0.227 ± 0.010M☉. The planet TIC 46432937 b is a warm super-Jupiter with a mass of 3.20 ± 0.11MJand radius of 1.188 ± 0.030RJ. The planet’s orbital period isP= 1.4404 days, and it undergoes grazing transits of its early M-dwarf host star, which has a mass of 0.563 ± 0.029M☉and a radius of 0.5299 ± 0.0091R☉. TIC 46432937 b is one of the highest-mass planets found to date transiting an M-dwarf star. TIC 46432937 b is also a promising target for atmospheric observations, having the highest transmission spectroscopy metric or emission spectroscopy metric value of any known warm super-Jupiter (mass greater than 3.0MJ, equilibrium temperature below 1000 K).
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This content will become publicly available on August 1, 2025
A hot-Jupiter progenitor on a super-eccentric retrograde orbit
Abstract Giant exoplanets orbiting close to their host stars are unlikely to have formed in their present configurations1. These ‘hot Jupiter’ planets are instead thought to have migrated inward from beyond the ice line and several viable migration channels have been proposed, including eccentricity excitation through angular-momentum exchange with a third body followed by tidally driven orbital circularization2,3. The discovery of the extremely eccentric (e = 0.93) giant exoplanet HD 80606 b (ref. 4) provided observational evidence that hot Jupiters may have formed through this high-eccentricity tidal-migration pathway5. However, no similar hot-Jupiter progenitors have been found and simulations predict that one factor affecting the efficacy of this mechanism is exoplanet mass, as low-mass planets are more likely to be tidally disrupted during periastron passage6–8. Here we present spectroscopic and photometric observations of TIC 241249530 b, a high-mass, transiting warm Jupiter with an extreme orbital eccentricity ofe = 0.94. The orbit of TIC 241249530 b is consistent with a history of eccentricity oscillations and a future tidal circularization trajectory. Our analysis of the mass and eccentricity distributions of the transiting-warm-Jupiter population further reveals a correlation between high mass and high eccentricity.
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- PAR ID:
- 10537585
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Nature Portfolio
- Date Published:
- Journal Name:
- Nature
- Volume:
- 632
- Issue:
- 8023
- ISSN:
- 0028-0836
- Page Range / eLocation ID:
- 50 to 54
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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