Biological, Equilibrium and Photochemical Signatures of C, N and S Isotopes in the Early Earth and Exoplanet Atmospheres. [PDF]
Life (Basel)The unambiguous detection of biosignatures in exoplanet atmospheres is a primary objective for astrobiologists and exoplanet astronomers. The primary methodology is the observation of combinations of gases considered unlikely to coexist in an atmosphere ...
Lyons JR.
europepmc +2 more sources
The air over there: exploring exoplanet atmospheres [PDF]
arXiv, 2021 Atmospheric compositions for rocky exoplanets will depend strongly on the bulk planetary composition and the orbital position of the planet. Non-traditional gases may be present in the atmospheres of exceptionally hot planets. Atmospheres of more clement planets will depend on the abundances of volatiles acquired during planet formation and atmospheric
Vivien Parmentier, Laura Schaefer
arxiv +5 more sources
Helium Atmospheres on Warm Neptune- and Sub-Neptune-Sized Exoplanets and Applications to GJ 436 b [PDF]
arXiv, 2015 Warm Neptune- and sub-Neptune-sized exoplanets in orbits smaller than Mercury's are thought to have experienced extensive atmospheric evolution. Here we propose that a potential outcome of this atmospheric evolution is the formation of helium-dominated atmospheres.
Hu, Renyu, Seager, Sara, Yung, Yuk L.
arxiv +6 more sources
HIGH RESOLUTION TRANSMISSION SPECTROSCOPY AS A DIAGNOSTIC FOR JOVIAN EXOPLANET ATMOSPHERES: CONSTRAINTS FROM THEORETICAL MODELS [PDF]
, 2014 We present high resolution transmission spectra of giant planet atmospheres from a coupled 3-D atmospheric dynamics and transmission spectrum model that includes Doppler shifts which arise from winds and planetary motion. We model jovian planets covering
Eliza M.-R. Kempton +2 more
openalex +3 more sources
Transiting Exoplanet Atmospheres in the Era of JWST [PDF]
arXivThe field of exoplanet atmospheric characterization has recently made considerable advances with the advent of high-resolution spectroscopy from large ground-based telescopes and the commissioning of the James Webb Space Telescope (JWST). We have entered an era in which atmospheric compositions, aerosol properties, thermal structures, mass loss, and ...
E. Kempton, H. Knutson
arxiv +2 more sources
Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS) [PDF]
Astronomy & Astrophysics, 2020 Ultra-hot Jupiters offer interesting prospects for expanding our theories on dynamical evolution and the properties of extremely irradiated atmospheres.
J. V. Seidel +19 more
semanticscholar +7 more sources
Photochemical Hazes Can Trace the C/O Ratio in Exoplanet Atmospheres [PDF]
Astrophysical Journal Letters, 2023 Photochemical hazes are suspected to obscure molecular features, such as water, from detection in the transmission spectra of exoplanets with atmospheric temperatures
L. Corrales +3 more
semanticscholar +1 more source
Optical properties of organic haze analogues in water-rich exoplanet atmospheres observable with JWST [PDF]
Nature Astronomy, 2023 JWST has begun its scientific mission, which includes the atmospheric characterization of transiting exoplanets. Some of the first exoplanets to be observed by JWST have equilibrium temperatures below 1000 K, which is a regime where photochemical hazes ...
Chao He +11 more
semanticscholar +1 more source
Photochemical Runaway in Exoplanet Atmospheres: Implications for Biosignatures [PDF]
Astrophysical Journal, 2022 About 2.5 billion years ago, microbes learned to harness plentiful solar energy to reduce CO2 with H2O, extracting energy and producing O2 as waste.
S. Ranjan +7 more
semanticscholar +1 more source
A Temperature Trend for Clouds and Hazes in Exoplanet Atmospheres [PDF]
Astrophysical Journal Letters, 2022 The transmission spectra of exoplanet atmospheres observed with the Hubble Space Telescope (HST) in the near-infrared range (1.1–1.65 μm) frequently show evidence for some combination of clouds and hazes.
R. Estrela, M. Swain, G. Roudier
semanticscholar +1 more source