Results 1 to 10 of about 804 (57)

CHEOPS observations of the HD 108236 planetary system: a fifth planet, improved ephemerides, and planetary radii [PDF]

Astronomy & Astrophysics, 2021
Context. The detection of a super-Earth and three mini-Neptunes transiting the bright (V = 9.2 mag) star HD 108236 (also known as TOI-1233) was recently reported on the basis of TESS and ground-based light curves. Aims.
A. Bonfanti, L. Delrez, M. Hooton, T. Wilson, L. Fossati, Y. Alibert, S. Hoyer, A. Mustill, H. Osborn, V. Adibekyan, D. Gandolfi, S. Salmon, S. Sousa, A. Tuson, V. Grootel, J. Cabrera, V. Nascimbeni, P. Maxted, S. Barros, N. Billot, X. Bonfils, L. Borsato, C. Broeg, M. Davies, M. Deleuil, O. Demangeon, M. Fridlund, G. Lacedelli, M. Lendl, C. Persson, N. Santos, G. Scandariato, G. Szab'o, A. Cameron, S. Udry, W. Benz, M. Beck, D. Ehrenreich, A. Fortier, K. Isaak, D. Queloz, R. Alonso, J. Asquier, T. Bandy, T. B'arczy, D. Barrado, O. Barrag'an, Wolfgang Baumjohann, T. Beck, A. Bekkelien, M. Bergomi, M. Busch, A. Brandeker, V. Cessa, S. Charnoz, B. Chazelas, C. V. Damme, B. Demory, A. Erikson, J. Farinato, D. Futyan, A. G. Muñoz, M. Gillon, M. Guedel, P. Guterman, J. Hasiba, K. Heng, E. Hernandez, L. Kiss, T. Kuntzer, J. Laskar, A. D. Étangs, C. Lovis, D. Magrin, L. Malvasio, L. Marafatto, H. Michaelis, M. Munari, G. Olofsson, H. Ottacher, R. Ottensamer, I. Pagano, E. Pall'e, G. Peter, D. Piazza, G. Piotto, D. Pollacco, R. Ragazzoni, N. Rando, F. Ratti, H. Rauer, I. Ribas, M. Rieder, R. Rohlfs, F. Safa, M. Salatti, D. S'egransan, A. Simon, A.M.S. Smith, M. Sordet, M. Steller, N. Thomas, M. Tschentscher, V. V. Eylen, V. Viotto, I. Walter, N. Walton, F. Wildi, D. Wolter   +108 more
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The case for studying other planetary magnetospheres and atmospheres in Heliophysics [PDF]

Vol. 55, Issue 3 (Heliophysics 2024 Decadal Whitepapers), 2023
Heliophysics is the field that"studies the nature of the Sun, and how it influences the very nature of space - and, in turn, the atmospheres of planetary bodies and the technology that exists there."However, NASA's Heliophysics Division tends to limit ...
I. Cohen, C. Arridge, A. Azari, C. Bard, G. Clark, F. Crary, S. Curry, P. Delamere, R. Dewey, G. DiBraccio, C. Dong, A. Drozdov, Austin Engert, Rachael J. Filwett, J. Halekas, A. Halford, A. Hughes, K. Garcia‐Sage, M. Gkioulidou, C. Goetz, C. Grava, M. Hirsch, H. Huybrighs, P. Kollmann, L. Lamy, Wen Li, M. Liemohn, R. Marshal, A. Masters, R. McAteer, Karan Molaverdikhani, A. Mukhopadhyay, R. Nikoukar, L. Paxton, L. Regoli, E. Roussos, N. Schneider, A. Sulaiman, Y. Sun, J. Szalay   +39 more
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Three planets transiting the evolved star EPIC 249893012: a hot 8.8-M⊕ super-Earth and two warm 14.7 and 10.2-M⊕ sub-Neptunes [PDF]

Astronomy & Astrophysics, 2020
We report the discovery of a new planetary system with three transiting planets, one super-Earth and two sub-Neptunes, that orbit EPIC 249893012, a G8 IV-V evolved star (M⋆ = 1.05 ± 0.05 M⊙, R⋆ = 1.71 ± 0.04 R⊙, Teff = 5430 ± 85 K).
D. Hidalgo, E. Pallé, R. Alonso, D. Gandolfi, M. Fridlund, G. Nowak, R. Luque, T. Hirano, A. B. Justesen, W. Cochran, O. Barragán, L. Spina, F. Rodler, S. Albrecht, D. Anderson, P. Amado, E. Bryant, J. Caballero, J. Cabrera, S. Csizmadia, F. Dai, J. D. Leon, H. Deeg, P. Eigmüller, M. Endl, A. Erikson, Massimiliano Esposito, P. Figueira, I. Georgieva, S. Grziwa, E. Guenther, A. Hatzes, M. Hjorth, H. J. Hoeijmakers, P. Kabáth, J. Korth, M. Kuzuhara, M. Lafarga, M. Lampón, I. Leão, J. Livingston, S. Mathur, P. Montañés-Rodríguez, J. Morales, F. Murgas, E. Nagel, N. Narita, L. Nielsen, M. Pätzold, C. Persson, J. Prieto-Arranz, A. Quirrenbach, H. Rauer, S. Redfield, A. Reiners, I. Ribas, Alexis M. S. Smith, J. Šubjak, V. V. Eylen, P. Wilson   +59 more
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Anatomy of planets formed by rapid pebble accretion. III. Partitioning of volatiles between planetary core, mantle, and atmosphere [PDF]

Astronomy & Astrophysics, 2022
Volatile molecules containing hydrogen, carbon, and nitrogen are key components of planetary atmospheres. In the pebble accretion model for rocky planet formation, these volatile species are accreted during the main planetary formation phase.
A. Johansen, T. Ronnet, M. Schiller, Z. Deng, M. Bizzarro   +4 more
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A low accretion efficiency of planetesimals formed at planetary gap edges [PDF]

Astronomy & Astrophysics, 2022
Observations and models of giant planets indicate that such objects are enriched in heavy elements compared to solar abundances. The prevailing view is that giant planets accreted multiple Earth masses of heavy elements after the end of core formation ...
L.E.J. Eriksson, T. Ronnet, A. Johansen, R. Helled, C. Valletta, A. C. Petit   +5 more
semanticscholar   +1 more source

Quantifying the Key Factors Affecting the Escape of Planetary Atmospheres

Astrophysical Journal, 2023
The habitability of Earth-like planets is an increasingly important subject in astrophysics and in planetary sciences. Atmospheric escape plays a vital role in the evolution of the habitability of Earth-like planets.
J. Luo, H.-Q. He, Gongsheng Tong, Jiao Li   +3 more
semanticscholar   +1 more source

Growth after the streaming instability: The radial distance dependence of the planetary growth [PDF]

Astronomy & Astrophysics, 2022
Streaming instability is hypothesized to be triggered at particular protoplanetary disk locations where the volume density of the solid particles is enriched comparable to that of the gas.
H. Jang, Beibei Liu, A. Johansen
semanticscholar   +1 more source

Formation of planetary systems by pebble accretion and migration [PDF]

Astronomy & Astrophysics, 2018
At least 30% of main sequence stars host planets with sizes of between 1 and 4 Earth radii and orbital periods of less than 100 days. We use N-body simulations including a model for gas-assisted pebble accretion and disk–planet tidal interaction to study
B. Bitsch, A. Izidoro, A. Johansen, S. Raymond, A. Morbidelli, M. Lambrechts, Seth Andrew Jacobson   +6 more
semanticscholar   +1 more source

Rossby Waves in Astrophysics

Space Science Reviews, 2021
Rossby waves are a pervasive feature of the large-scale motions of the Earth’s atmosphere and oceans. These waves (also known as planetary waves and r-modes) also play an important role in the large-scale dynamics of different astrophysical objects such ...
T. V. Zaqarashvili, M. Albekioni, J. Ballester, Y. Bekki, L. Biancofiore, A. Birch, M. Dikpati, L. Gizon, E. Gurgenashvili, E. Heifetz, Antonino Francesco Lanza, S. McIntosh, L. Ofman, R. Oliver, B. Proxauf, O. Umurhan, R. Yellin-Bergovoy   +16 more
semanticscholar   +1 more source

Venus as an anchor point for planetary habitability [PDF]

Nature Astronomy
A major focus of the planetary science and astrobiology community is the understanding of planetary habitability, including the myriad factors that control the evolution and sustainability of temperate surface environments such as that of Earth.
Stephen R. Kane, Paul K. Byrne
semanticscholar   +1 more source