Results 41 to 50 of about 10,220 (206)

Fleeting but Not Forgotten: The Imprint of Escaping Hydrogen Atmospheres on Super-Earth Interiors

The Astrophysical Journal
Small, close-in exoplanets are divided into two subpopulations: super-Earths and sub-Neptunes. Most super-Earths are thought to have lost their primordially accreted hydrogen-dominated atmospheres via thermally driven winds.
James G. Rogers, Hilke E. Schlichting, Edward D. Young   +2 more
doaj   +1 more source

Mapping out the time-evolution of exoplanet processes [PDF]

, 2019
There are many competing theories and models describing the formation, migration and evolution of exoplanet systems. As both the precision with which we can characterize exoplanets and their host stars, and the number of systems for which we can make ...
Beichman, Charles, Christiansen, Jessie L., Ciardi, David R., Huber, Daniel, Marley, Mark S.   +4 more
core   +1 more source

Exoplanet albedo spectra and colors as a function of planet phase, separation, and metallicity [PDF]

, 2010
First generation optical coronagraphic telescopes will obtain images of cool gas and ice giant exoplanets around nearby stars. The albedo spectra of exoplanets at planet-star separations larger than about 1 AU are dominated by reflected light to beyond 1
Ackerman, Alibert, Beichman, Boss, Brown, Burrows, Burrows, Burrows, Chapman, Chapman, Conrath, Dlugach, Dodson-Robinson, Dyudina, Fortney, Fortney, Fortney, Fortney, Fortney, Fortney, Freedman, Gautier, Gautier, Guillot, Guillot, Guyon, Ida, Jonathan J. Fortney, Kasdin, Kerri L. Cahoy, Kratter, Kuchner, Lafreniere, Liou, Lodders, Lodders, Lodders, Mark S. Marley, Marley, Marley, Marley, Marley, Marois, Mawet, Mihilas, Rauscher, Saumon, Saumon, Seager, Sobolev, Spiegel, Stephens, Sudarsky, Sudarsky, Sudarsky, Traub, Veras, West, Zahnle   +58 more
core   +2 more sources

Constraining Atmospheric Composition from the Outflow: Helium Observations Reveal the Fundamental Properties of Two Planets Straddling the Radius Gap

The Astronomical Journal
TOI-836 is a ∼2–3 Gyr K dwarf with an inner super Earth ( R  = 1.7 R _⊕ , P = 3.8 days) and an outer mini-Neptune ( R  = 2.6 R _⊕ , P = 8.6 days). JWST/NIRSpec 2.8–5.2 μ m transmission spectra are flat for both planets.
Michael Zhang, Jacob L. Bean, David Wilson, Girish Duvvuri, Christian Schneider, Heather A. Knutson, Fei Dai, Karen A. Collins, Cristilyn N. Watkins, Richard P. Schwarz, Khalid Barkaoui, Avi Shporer, Keith Horne, Ramotholo Sefako, Felipe Murgas, Enric Palle   +15 more
doaj   +1 more source

The Exoplanet Population Observation Simulator. II -- Population Synthesis in the Era of Kepler [PDF]

, 2019
The collection of planetary system properties derived from large surveys such as Kepler provides critical constraints on planet formation and evolution.
Apai, Daniel, Ciesla, Fred J., Emsenhuber, Alexandre, Mordasini, Christoph, Mulders, Gijs D., Pascucci, Ilaria   +5 more
core   +3 more sources

Helium Depletion in Escaping Atmospheres of Sub-Neptunes: A Signature of Primary-to-secondary Transition

The Astrophysical Journal
Short-period sub-Neptunes are common in extrasolar systems. These sub-Neptunes are generally thought to have primary atmospheres of protoplanetary-disk gas origin.
Issei Kobayashi, Hiroyuki Kurokawa, Laura Schaefer, Satoshi Okuzumi   +3 more
doaj   +1 more source

Outflowing Helium from a Mature Mini-Neptune

The Astrophysical Journal Letters, 2023
We announce the detection of escaping helium from TOI 2134b, a mini-Neptune a few gigayears old. The average in-transit absorption spectrum shows a peak of 0.37% ± 0.05% and an equivalent width of W _avg = 3.3 ± 0.3 mÅ.
Michael Zhang, Fei Dai, Jacob L. Bean, Heather A. Knutson, Federica Rescigno   +4 more
doaj   +1 more source

A Helicity-Based Method to Infer the CME Magnetic Field Magnitude in Sun and Geospace: Generalization and Extension to Sun-Like and M-Dwarf Stars and Implications for Exoplanet Habitability

, 2017
Patsourakos et al. (Astrophys. J. 817, 14, 2016) and Patsourakos and Georgoulis (Astron. Astrophys. 595, A121, 2016) introduced a method to infer the axial magnetic field in flux-rope coronal mass ejections (CMEs) in the solar corona and farther away in ...
A. Isavnin, A. Kumar, A. Nindos, A. Nindos, A. Nindos, A. Thernisien, A. Vourlidas, A.A. Vidotto, A.A. Vidotto, A.N. Aarnio, B. Gladman, B. Kliem, B. Vrsnak, B. Vršnak, B.E. Wood, B.J. Lynch, B.J. Lynch, B.J. Lynch, B.M. Jakosky, C. Cid, C. Garraffo, C. Karoff, C. Kay, C. Kay, C. Möstl, C.-C. Wu, C.H. Mandrini, C.J. Schrijver, C.R. DeVore, D. Cunha, D. Nogami, D.J. Armstrong, E. Bosman, E. Pariat, E.A. Jensen, E.R. Houdebine, E.R. Priest, E.W. Cliver, F. Selsis, G. Anglada-Escudé, G. Aulanier, G. Chintzoglou, G. Torres, G. Valori, G.A. Gary, H. Lammer, H. Maehara, I.G. Usoskin, J. Leconte, J. Scalo, J.-F. Donati, J.-M. Grießmeier, J.-M. Grießmeier, J.F. Kasting, J.J. Drake, J.R.A. Davenport, K. Hariharan, K. Moraitis, K. Shibata, K. Tziotziou, K. Tziotziou, L.K. Harra, L.M. Green, M. Leitner, M. Leitzinger, M. Leitzinger, M. Patzold, M. Semel, M. Vandas, M.A. Berger, M.A. Hidalgo, M.D. Andrews, M.D. Kazachenko, M.K. Georgoulis, M.K. Georgoulis, M.L. Khodachenko, M.L. Luoni, M.S. Nakwacki, N. Al-Haddad, N.P. Savani, P. Démoulin, P. Démoulin, P. Démoulin, P. MacNeice, P. Riley, Q. Hu, R. Kataoka, R. Osten, R.A. Osten, R.J. Forsyth, R.M. Winslow, R.P. Lepping, S. Chapman, S. Dasso, S. Lundquist, S. Mancuso, S. Patsourakos, S. Patsourakos, S. Régnier, S. Toriumi, S. Yashiro, S.D. Tun, S.E. Gibson, S.R. Kane, S.W. Good, T. Gold, T. Nieves-Chinchilla, T. Shibayama, T.A. Howard, T.G. Forbes, T.S. Bastian, V. Bothmer, V. Kunkel, V. See, V.S. Airapetian, W. Poomvises, X. Sun, Y. Guo, Y. Liu, Y. Wang   +119 more
core   +1 more source

Laboratory spectra of hot molecules: data needs for hot super-Earth exoplanets [PDF]

, 2017
The majority of stars are now thought to support exoplanets. Many of those exoplanets discovered thus far are categorized as rocky objects with an atmosphere. Most of these objects are however hot due to their short orbital period.
Tennyson, Jonathan, Yurchenko, Sergei N.
core   +2 more sources

Stellar Driven Evolution of Hydrogen-Dominated Atmospheres from Earth-Like to Super-Earth-Type Exoplanets [PDF]

, 2014
Originally published by: Springer International Publishing Switzerland 2015 H. Lammer, M. Khodachenko (eds.), Characterizing Stellar and Exoplanetary Environments, Astrophysics and Space Science Library ...
Kislyakova, K. G., Holmström, M., Lammer, H., Erkaev, N. V.   +3 more
openaire   +2 more sources