Results 61 to 70 of about 53,484 (152)

Controls of Atmospheric Methane on Early Earth and Inhabited Earth-like Terrestrial Exoplanets [PDF]

, 2023
Methane (CH4) is a primarily biogenic greenhouse gas. As such, it represents an essential biosignature to search for life on exoplanets. Atmospheric CH4 abundance on Earth-like inhabited exoplanets is likely controlled by marine biogenic production and atmospheric photochemical consumption.
arxiv   +1 more source

Hα Absorption in Transiting Exoplanet Atmospheres [PDF]

Proceedings of the International Astronomical Union, 2013
AbstractRecent observations by Jensen et al. of Hα absorption by the upper atmosphere of HD189733b have motivated the need for a theoretical understanding of the distribution of n=2 hydrogen within hot Jupiter atmospheres. With this in mind, we model the n=2 state of atomic hydrogen in a hydrostatic atmosphere in thermal and photoionization equilibrium.
Phil Arras, Zhi-Yun Li, Duncan Christie
openaire   +5 more sources

A Radiative-convective Model for Terrestrial Planets with Self-consistent Patchy Clouds

The Planetary Science Journal, 2023
Clouds are ubiquitous: they arise for every solar system planet that possesses an atmosphere and have also been suggested as a leading mechanism for obscuring spectral features in exoplanet observations.
James D. Windsor, Tyler D. Robinson, Ravi kumar Kopparapu, Amber V. Young, David E. Trilling, Joe LLama   +5 more
doaj   +1 more source

The role of boundary‐layer friction in modulating midlatitude heatwaves

Quarterly Journal of the Royal Meteorological Society, EarlyView.
Boundary‐layer friction associated with different surface types plays an important role in modulating heatwaves in the midlatitudes. The main changes in heatwave features occur when locally modifying boundary‐layer friction along the jet‐stream axis. Real‐world differences in the occurrence of heatwaves between different locations in the midlatitudes ...
E. Russo, W. Wicker, D. Folini, D. I. V. Domeisen   +3 more
wiley   +1 more source

Hubble Space Telescope Transmission Spectroscopy for the Temperate Sub-Neptune TOI-270 d: A Possible Hydrogen-rich Atmosphere Containing Water Vapor

The Astronomical Journal, 2023
TOI-270 d is a temperate sub-Neptune discovered by the Transiting Exoplanet Survey Satellite (TESS) around a bright ( J = 9.1 mag) M3V host star. With an approximate radius of 2 R _⊕ and equilibrium temperature of 350 K, TOI-270 d is one of the most ...
Thomas Mikal-Evans, Nikku Madhusudhan, Jason Dittmann, Maximilian N. Günther, Luis Welbanks, Vincent Van Eylen, Ian J. M. Crossfield, Tansu Daylan, Laura Kreidberg   +8 more
doaj   +1 more source

Exoplanet phase curves: observations and theory

, 2018
Phase curves are the best technique to probe the three dimensional structure of exoplanets' atmospheres. In this chapter we first review current exoplanets phase curve observations and the particular challenges they face.
A Shporer, A Shporer, Adam P. Showman, AP Showman, AP Showman, AP Showman, BO Demory, BO Demory, C Visscher, Curtis S. Cooper, D Perez-Becker, D Piskorz, D. J. Armstrong, DDB Koll, F Selsis, HA Knutson, HA Knutson, Heather A. Knutson, I Hubeny, Ian Wong, Ian Wong, IJM Crossfield, IJM Crossfield, IJM Crossfield, J Harrington, J Langton, J Leconte, J Leconte, J Wit de, J Yang, J. C. Schwartz, JC Schwartz, JE Krick, JJ Fortney, K Batygin, K Haynes, K Heng, K Heng, KB Stevenson, KB Stevenson, KB Stevenson, KB Stevenson, Kevin B. Stevenson, L Kreidberg, Lisa J. Esteves, M Agúndez, M Oreshenko, MR Line, MW Webber, N Iro, NB Cowan, NB Cowan, NB Cowan, Nicolas B. Cowan, NK Lewis, NK Lewis, P Hut, PFL Maxted, R Hu, R Perna, R Perna, Robert T. Zellem, RT Pierrehumbert, S Fromang, S Millholland, SM Tsai, SR Kane, T Guillot, T Kataria, T Kataria, TD Komacek, Thaddeus D. Komacek, TM Evans, TM Rogers, TM Rogers, UA Dyudina, V Parmentier, Vivien Parmentier, Vivien Parmentier, Vivien Parmentier, X Zhang, YK Feng   +81 more
core   +1 more source

CHARACTERIZING TRANSITING EXOPLANET ATMOSPHERES WITH JWST [PDF]

The Astrophysical Journal, 2016
ABSTRACT We explore how well spectra from the James Webb Space Telescope (JWST) will likely constrain bulk atmospheric properties of transiting exoplanets. We start by modeling the atmospheres of archetypal hot Jupiter, warm Neptune, warm sub-Neptune, and cool super-Earth planets with atmospheres that are clear, cloudy, or of high mean ...
Greene, Thomas P, Line, Michael R, Montero, Cezar, Fortney, Jonathan J, Lustig-Yaeger, Jacob, Luther, Kyle   +5 more
openaire   +5 more sources

The Importance of Optical Wavelength Data on Atmospheric Retrievals of Exoplanet Transmission Spectra

The Astronomical Journal
Exoplanet transmission spectra provide rich information about the chemical composition, clouds, and temperature structure of exoplanet atmospheres. Most exoplanet transmission spectra only span infrared wavelengths (≳1 μ m), which can preclude crucial ...
Charlotte Fairman, Hannah R. Wakeford, Ryan J. MacDonald   +2 more
doaj   +1 more source

Tracing the Contribution of Abiotic Methane in Deep Natural Gases From the Songliao Basin, China Using Bulk Isotopes and Methane Clumped Isotopologue 12CH2D2

Geochemistry, Geophysics, Geosystems, Volume 26, Issue 4, April 2025.
Abstract The identification and evaluation of abiotic methane remain an active research area due to uncertainties in traditional indicators that may lead to “false‐positive” detections. As an emerging isotopic tool, methane clumped isotope can provide novel information about the generation and post‐generation processes of methane gases.
Jiacheng Li, Qingmei Liu, Wenmin Jiang, Yun Li, Yanhua Shuai, Yongqiang Xiong   +5 more
wiley   +1 more source

Ground-based Reconnaissance Observations of 21 Exoplanet Atmospheres with the Exoplanet Transmission Spectroscopy Imager

The Astronomical Journal
One of the most prolific methods of studying exoplanet atmospheres is transmission spectroscopy, which measures the difference between the depth of an exoplanet's transit signal at various wavelengths and attempts to correlate the depth changes to ...
Ryan J. Oelkers, Luke M. Schmidt, Erika Cook, Mary Anne Limbach, D. L. DePoy, J. L. Marshall, Jimmy Ardoin, Mitchell Barry, Evan Batteas, Alexandra Boone, Brant Conway, Silvana Delgado Adrande, John D. Dixon, Enrique Gonzalez-Vega, Alexandra Guajardo, Landon Holcomb, Christian Lambert, Shravan Menon, Divya Mishra, Jacob Purcell, Zachary Reed, Nathan Sala, Noah Siebersma, Nhu Ngoc Ton, Raenessa M. L. Walker, Z. Franklin Wang, Kaitlin Webber   +26 more
doaj   +1 more source