A super-massive Neptune-sized planet
Abstract
Neptune-sized planets exhibit a wide range of compositions and densities, depending onf cators related to their formation and evolution history, such as the distance from their host stars and atmospheric escape processes. They can vary from relatively low-density planets with thick hydrogen-helium atmospheres to higher-density planets with a substantial amount of water or a rocky interior with a thinner atmosphere, such as HD 95338 b, TOI-849 b and TOI-2196 b. The discovery of exoplanets in the hot-Neptune desert, a region close to the host stars with a deficit of Neptune-sized planets, provides insights into the formation and evolution of planetary systems, including the existence of this region itself. Here we show observations of the transiting planet TOI-1853 b, which has a radius of 3.46 +- 0.08 Earth radii and orbits a dwarf star every 1.24 days. This planet has a mass of 73.2 +- 2.7 Earth masses, almost twice that of any other Neptune-sized planet known so far, and a density of 9.7 +- 0.8 grams per cubic centimetre. These values place TOI-1853 b in the middle of the Neptunian desert and imply that heavy elements dominate its mass. The properties of TOI-1853 b present a puzzle for conventional theories of planetary formation and evolution, and could be the result of several proto-planet collisions or the final state of an initially high-eccentricity planet that migrated closer to its parent star.
Cite
@article{arxiv.2309.01464,
title = {A super-massive Neptune-sized planet},
author = {L. Naponiello and L. Mancini and A. Sozzetti and A. S. Bonomo and A. Morbidelli and J. Dou and L. Zeng and Z. M. Leinhardt and K. Biazzo and P. Cubillos and M. Pinamonti and D. Locci and A. Maggio and M. Damasso and A. F. Lanza and J. J. Lissauer and A. Bignamini and W. Boschin and L. G. Bouma and P. J. Carter and D. R. Ciardi and K. A. Collins and R. Cosentino and I. Crossfield and S. Desidera and X. Dumusque and A. F. M. Fiorenzano and A. Fukui and P. Giacobbe and C. L. Gnilka and A. Ghedina and E. Gonzales and G. Guilluy and A. Harutyunyan and S. B. Howell and J. M. Jenkins and M. B. Lund and E. L. N. Jensen and J. F. Kielkopf and K. V. Lester and L. Malavolta and A. W. Mann and R. A. Matson and E. C. Matthews and D. Nardiello and N. Narita and E. Pace and I. Pagano and E. Palle and M. Pedani and S. Seager and J. E. Schlieder and R. P. Schwarz and A. Shporer and J. D. Twicken and J. N. Winn and C. Ziegler and T. Zingales},
journal= {arXiv preprint arXiv:2309.01464},
year = {2023}
}
Comments
Preprint submitted to Nature. Please refer to the published version for the final parameters estimations