Atmospheres of Rocky Exoplanets
نویسندگان
چکیده
Rocky planets are common around other stars, but their atmospheric properties remain largely unconstrained. Thanks to a wealth of recent planet discoveries and upcoming advances in observing capability, we poised characterize the atmospheres dozens rocky exoplanets this decade. Theoretical understanding exoplanet has advanced considerably last few years, yielding testable predictions evolution, chemistry, dynamics even possible biosignatures. Here review key progress field date discuss future objectives. Our major conclusions as follows: 1) Many may form with initial H$_2$-He envelopes that later lost space, likely due combination stellar UV/X-ray irradiation internal heating. 2) After early stages wide diversity compositions is expected, variations host star flux, escape rates, interior exchange factors. 3) Observations have ruled out presence hydrogen-dominated on several nearby exoplanets, any thick atmosphere one target. More detailed characterization these others will become near future. 4) Exoplanet biosphere searches an exciting goal. However, reliable detections for representative sample require further capability improvements our abiotic planetary processes.
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ژورنال
عنوان ژورنال: Annual Review of Astronomy and Astrophysics
سال: 2022
ISSN: ['1545-4282', '0066-4146']
DOI: https://doi.org/10.1146/annurev-astro-052920-125632