Journal articles on the topic 'Atmosphere'
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1
Sergeev, Denis E., Nathan J. Mayne, Thomas Bendall, Ian A. Boutle, Alex Brown, Iva Kavčič, James Kent, et al. "Simulations of idealised 3D atmospheric flows on terrestrial planets using LFRic-Atmosphere." Geoscientific Model Development 16, no. 19 (October 10, 2023): 5601–26. http://dx.doi.org/10.5194/gmd-16-5601-2023.
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Abstract. We demonstrate that LFRic-Atmosphere, a model built using the Met Office's GungHo dynamical core, is able to reproduce idealised large-scale atmospheric circulation patterns specified by several widely used benchmark recipes. This is motivated by the rapid rate of exoplanet discovery and the ever-growing need for numerical modelling and characterisation of their atmospheres. Here we present LFRic-Atmosphere's results for the idealised tests imitating circulation regimes commonly used in the exoplanet modelling community. The benchmarks include three analytic forcing cases: the standard Held–Suarez test, the Menou–Rauscher Earth-like test, and the Merlis–Schneider tidally locked Earth test. Qualitatively, LFRic-Atmosphere agrees well with other numerical models and shows excellent conservation properties in terms of total mass, angular momentum, and kinetic energy. We then use LFRic-Atmosphere with a more realistic representation of physical processes (radiation, subgrid-scale mixing, convection, clouds) by configuring it for the four TRAPPIST-1 Habitable Atmosphere Intercomparison (THAI) scenarios. This is the first application of LFRic-Atmosphere to a possible climate of a confirmed terrestrial exoplanet. LFRic-Atmosphere reproduces the THAI scenarios within the spread of the existing models across a range of key climatic variables. Our work shows that LFRic-Atmosphere performs well in the seven benchmark tests for terrestrial atmospheres, justifying its use in future exoplanet climate studies.
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Ragossnig, Florian, Alexander Stökl, Ernst Dorfi, Colin P. Johnstone, Daniel Steiner, and Manuel Güdel. "Interaction of infalling solid bodies with primordial atmospheres of disk-embedded planets." Astronomy & Astrophysics 618 (October 2018): A19. http://dx.doi.org/10.1051/0004-6361/201832681.
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Context. Planets that form early enough to be embedded in the circumstellar gas disk accumulate thick atmospheres of nebular gas. Models of these atmospheres need to specify the surface luminosity (i.e. energy loss rate) of the planet. This luminosity is usually associated with a continuous inflow of solid bodies, where the gravitational energy released from these bodies is the source of energy. However, if these bodies release energy in the atmosphere instead of at the surface, this assumption might not be justified. Aims. Our aim is to explore the interactions of infalling planetesimals with primordial atmospheres at an embedded phase of evolution. We investigate effects of atmospheric interaction on the planetesimals (mass loss) and the atmosphere (heating/cooling). Methods. We used atmospheric parameters from a snapshot of time-dependent evolution simulations for embedded atmospheres and simulated purely radial, infall events of siliceous planetesimals in a 1D, explicit code. We implemented energy transfer between friction, radiation transfer by the atmosphere and the body, and thermal ablation; this gives us the possibility to examine the effects on the planetesimals and the atmosphere. Results. We find that a significant amount of gravitational energy is indeed dissipated into the atmosphere, especially for larger planetary cores, which consequently cannot contribute to the atmospheric planetary luminosity. Furthermore, we examine that planetesimal infall events for cores, MC > 2M⊕, which actually result in a local cooling of the atmosphere; this is totally in contradiction with the classical model.
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Chouqar, J., Z. Benkhaldoun, A. Jabiri, J. Lustig-Yaeger, A. Soubkiou, and A. Szentgyorgyi. "Properties of sub-Neptune atmospheres: TOI-270 system." Monthly Notices of the Royal Astronomical Society 495, no. 1 (May 2, 2020): 962–70. http://dx.doi.org/10.1093/mnras/staa1198.
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ABSTRACT We investigate the potential for the James Webb Space Telescope (JWST) to detect and characterize the atmospheres of the sub-Neptunian exoplanets in the TOI-270 system. Sub-Neptunes are considered more likely to be water worlds than gas dwarfs. We model their atmospheres using three atmospheric compositions – two examples of hydrogen-dominated atmospheres and a water-dominated atmosphere. We then simulate the infrared transmission spectra of these atmospheres for JWST instrument modes optimized for transit observation of exoplanet atmospheres: NIRISS, NIRSpec, and MIRI. We then predict the observability of each exoplanet’s atmosphere. TOI-270c and d are excellent targets for detecting atmospheres with JWST transmission spectroscopy, requiring only 1 transit observation with NIRISS, NIRSpec, and MIRI; higher signal-to-noise ratio can be obtained for a clear H-rich atmosphere. Fewer than three transits with NIRISS and NIRSpec may be enough to reveal molecular features. Water-dominated atmospheres require more transits. Water spectral features in water-dominated atmospheres may be detectable with NIRISS in two or three transits. We find that the detection of spectral features in a cloudy, H-rich atmosphere does not require integrations as long as those required for the water-dominated atmosphere, which is consistent with the differences in atmospheric mean molecular weight. TOI-270c and d could be prime targets for JWST transit observations of sub-Neptune atmospheres. These results provide useful predictions for observers who may propose to use JWST to detect and characterize the TOI-270 planet atmospheres.
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Sysoeva, Yu V. "Проблема атмосферы у Г. Беме и ее отношение к цифровой культуре." Studia Culturae, no. 56 (November 2, 2023): 120. http://dx.doi.org/10.31312/2310-1245-2023-56-120-143.
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This article is devoted to a relatively new aesthetic concept, the concept of atmosphere. In the second half of the 20th century, due to the overcoming of the understanding of the aesthetic as a field of art and the emergence of the tendency to appeal to sensual experience, the idea that aesthetic perception and aesthetic experience are possible not only in the context of art events, but also in the space of everyday life is becoming increasingly relevant. The aesthetics of atmosphere arises from the aesthetics of everyday life. The first to declare the concept of atmosphere as a separate aesthetic theory was H. Böhme (1937–2022). The immediate predecessors of the concept of atmospheres are the theoretical positions of G. Schmitz and W. Benjamin. The aesthetics of atmospheres explores the states that arise in the process of the relationship between the subjective and the objective factors and in their material, emotional interaction. This article analyzes H. Beme’s concept of atmosphere, as presented by him in his works: “‘Atmosphere’ as a fundamental concept of the new aesthetics”, “Atmospheric Architectures: The Aesthetics of Felt Spaces”, “Architektur und Atmosphäre”. A special place in H. Beme’s aesthetic theory of atmospheres is occupied, first, by the concept of “ecstasy of things” introduced by him, which allows us to speak of the relatively objective nature of atmospheres, and, second, by the problem of the production of artificial atmospheres. Most studies of atmosphere as an aesthetic category consider atmosphere in the context of architecture, urban environment, design, etc. This article attempts to explore the atmosphere in digital space. At present, digital space has already lost its representational and in principle auxiliary position in relation to the human being, and has become a space for the realization of possibilities, the functioning of which was not represented in the human being’s being. The specific possibilities of the digital require a special analysis of the aesthetic, capable of exploring the digital space in its entirety. The article suggests that the concept of atmospheres is a productive way to work with digital space, which is shown on the example of such digital space phenomena as metavelves and ASMR-video. The study showed that the concept of atmospheres is convenient for working with digital space, especially due to the fact that with its help it is possible to carry out successful analysis not only of visual and auditory components (characteristic for classical aesthetics), but also of other ways of aesthetic perception.
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Seager, Sara. "Exoplanet atmospheres: A theoretical outlook." Proceedings of the International Astronomical Union 6, S276 (October 2010): 198–207. http://dx.doi.org/10.1017/s1743921311020187.
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AbstractWith over two dozen exoplanet atmospheres observed today, the field of exoplanet atmospheres is solidly established. The highlights of exoplanet atmosphere studies include: detection of molecular spectral features; constraints on atmospheric vertical temperature structure; detection of day-night temperature gradients; and a new numerical approach to atmosphere temperature and abundance retrieval. As hot Jupiter observations and interpretation are maturing, the next frontier is super Earth atmospheres. Theoretical models of super Earth atmospheres are moving forward with observational hopes pinned on the James Webb Space Telescope, scheduled for launch in 2014. Further in the future lies direct imaging attempts to answer the enigmatic and ancient question, “Are we alone?” via atmospheric biosignatures.
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Miller-Ricci, Eliza, Sara Seager, and Dimitar Sasselov. "The Atmospheres of Extrasolar Super-Earths." Proceedings of the International Astronomical Union 4, S253 (May 2008): 263–71. http://dx.doi.org/10.1017/s1743921308026483.
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AbstractExtrasolar super-Earths (1-10 M⊕) are likely to exist with a wide range of atmospheres. While a number of these planets have already been discovered through radial velocities and microlensing, it will be the discovery of the firsttransitingsuper-Earths that will open the door to a variety of follow-up observations aimed at characterizing their atmospheres. Super-Earths may fill a large range of parameter space in terms of their atmospheric composition and mass. Specifically, some of these planets may have high enough surface gravities to be able to retain large hydrogen-rich atmosphseres, while others will have lost most of their hydrogen to space over the planet's lifetime, leaving behind an atmosphere more closely resembling that of Earth or Venus. The resulting composition of the super-Earth atmosphere will therefore depend strongly on factors such as atmospheric escape history, outgassing history, and the level of stellar irradiation that it receives. Here we present theoretical models of super-Earth emission and transmission spectra for a variety of possible outcomes of super-Earth atmospheric composition ranging from hydrogen-rich to hydrogen-poor. We focus on how observations can be used to differentiate between the various scenarios and constrain atmospheric composition.
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Bisikalo, Dmitri, Valery Shematovich, and Benoit Hubert. "The Kinetic Monte Carlo Model of the Auroral Electron Precipitation into N2-O2 Planetary Atmospheres." Universe 8, no. 8 (August 22, 2022): 437. http://dx.doi.org/10.3390/universe8080437.
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Auroral events are the prominent manifestation of solar/stellar forcing on planetary atmospheres. They are closely related to the energy deposition by and evolution of planetary atmospheres, and their observations are widely used to analyze the composition, structure, and chemistry of the atmosphere under study, as well as energy fluxes of the precipitating particles that affect the atmosphere. A numerical kinetic Monte Carlo model had been developed, allowing us to study the processes of precipitation of high-energy auroral electrons into the N2-O2 atmospheres of the rocky planets in the Solar and exosolar planetary systems. This model describes on a molecular level the collisions of auroral electrons and atmospheric gas, taking into account the stochastic nature of collisional scattering at high kinetic energies. The current status of the kinetic model is illustrated in the applications to the auroral events on the Earth such as the production of suprathermal nitrogen atoms due to the electron impact dissociation of N2. It was found that electron impact dissociation of N2 can potentially be an important source of suprathermal N atoms in the auroral regions of the N2-O2 atmosphere of terrestrial-type planets. Such research will allow us to study the odd nitrogen chemistry as an atmospheric marker of the N2-O2 atmosphere of rocky exoplanets.
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Kurosaki, Kenji, and Shu-ichiro Inutsuka. "Giant Impact Events for Protoplanets: Energetics of Atmospheric Erosion by Head-on Collision." Astrophysical Journal 954, no. 2 (September 1, 2023): 196. http://dx.doi.org/10.3847/1538-4357/ace9ba.
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Abstract Numerous exoplanets with masses ranging from Earth to Neptune and radii larger than Earth have been found through observations. These planets possess atmospheres that range in mass fractions from 1% to 30%, reflecting the diversity of atmospheric mass fractions. Such diversities are supposed to be caused by differences in the formation processes or evolution. Here, we consider head-on giant impacts onto planets causing atmosphere losses in the later stage of their formation. We perform smoothed particle hydrodynamic simulations to study the impact-induced atmosphere loss of young super-Earths with 10%–30% initial atmospheric mass fractions. We find that the kinetic energy of the escaping atmosphere is almost proportional to the sum of the kinetic impact energy and self-gravitational energy released from the merged core. We derive the relationship between the kinetic impact energy and the escaping atmosphere mass. The giant impact events for planets of comparable masses are required in the final stage of the popular scenario of rocky planet formation. We show it results in a significant loss of the atmosphere, if the impact is a head-on collision with comparable masses. This latter fact provides a constraint on the formation scenario of rocky planets with substantial atmospheres.
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Johnstone, Colin P. "The Influences of Stellar Activity on Planetary Atmospheres." Proceedings of the International Astronomical Union 12, S328 (October 2016): 168–79. http://dx.doi.org/10.1017/s1743921317003775.
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AbstractOn evolutionary timescales, the atmospheres of planets evolve due to interactions with the planet's surface and with the planet's host star. Stellar X-ray and EUV (=’XUV’) radiation is absorbed high in the atmosphere, driving photochemistry, heating the gas, and causing atmospheric expansion and mass loss. Atmospheres can interact strongly with the stellar winds, leading to additional mass loss. In this review, I summarise some of the ways in which stellar output can influence the atmospheres of planets. I will discuss the importance of simultaneously understanding the evolution of the star's output and the time dependent properties of the planet's atmosphere.
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Chowdhury, Sohini, Yadaiah Nirsanametla, and Muralidhar Manapuram. "Investigation on keyhole mode fiber laser welding of SS 316 in a self-protected atmosphere." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 18 (July 19, 2019): 6602–15. http://dx.doi.org/10.1177/0954406219864137.
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This work focuses on examining the influence of welding parameters under different welding atmospheres and evaluation of keyhole profile during fiber laser welding operation. The experiments are carried out in two different welding atmospheres, namely self-protected atmosphere of Ar gas and open atmospheric conditions. The effect of these two atmospheric conditions on weld profile formation and dimensions, and microstructural evolution for SS 316 plates are examined. In addition, the keyhole profile is evaluated by using a semi-analytical mathematical model, a point-by-point energy balance determination at the keyhole wall, which is mapped with experimentally measured weld macrographs for similar welding conditions. It has been determined that the weld quality is profound in the case of a self-protected atmosphere with respect to aspect ratio, weld defects, and microstructural characterization. Moreover, better weld bead profile and cleaner weld seam on the upper surface is determined in samples welded in a self-protected atmosphere.
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Sinclair, Catriona A., Mark C. Wyatt, Alessandro Morbidelli, and David Nesvorný. "Evolution of the Earth’s atmosphere during Late Veneer accretion." Monthly Notices of the Royal Astronomical Society 499, no. 4 (October 16, 2020): 5334–62. http://dx.doi.org/10.1093/mnras/staa3210.
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ABSTRACT Recent advances in our understanding of the dynamical history of the Solar system have altered the inferred bombardment history of the Earth during accretion of the Late Veneer, after the Moon-forming impact. We investigate how the bombardment by planetesimals left-over from the terrestrial planet region after terrestrial planet formation, as well as asteroids and comets, affects the evolution of Earth’s early atmosphere. We develop a new statistical code of stochastic bombardment for atmosphere evolution, combining prescriptions for atmosphere loss and volatile delivery derived from hydrodynamic simulations and theory with results from dynamical modelling of realistic populations of impactors. We find that for an initially Earth-like atmosphere, impacts cause moderate atmospheric erosion with stochastic delivery of large asteroids, giving substantial growth (× 10) in a few ${{\ \rm per\ cent}}$ of cases. The exact change in atmosphere mass is inherently stochastic and dependent on the dynamics of the left-over planetesimals. We also consider the dependence on unknowns including the impactor volatile content, finding that the atmosphere is typically completely stripped by especially dry left-over planetesimals ($\lt 0.02 ~ {{\ \rm per\ cent}}$ volatiles). Remarkably, for a wide range of initial atmosphere masses and compositions, the atmosphere converges towards similar final masses and compositions, i.e. initially low-mass atmospheres grow, whereas massive atmospheres deplete. While the final properties are sensitive to the assumed impactor properties, the resulting atmosphere mass is close to that of current Earth. The exception to this is that a large initial atmosphere cannot be eroded to the current mass unless the atmosphere was initially primordial in composition.
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Hu, Renyu, Fabrice Gaillard, and Edwin S. Kite. "Narrow Loophole for H2-Dominated Atmospheres on Habitable Rocky Planets around M Dwarfs." Astrophysical Journal Letters 948, no. 2 (May 1, 2023): L20. http://dx.doi.org/10.3847/2041-8213/acd0b4.
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Abstract Habitable rocky planets around M dwarfs that have H2-dominated atmospheres, if they exist, would permit characterizing habitable exoplanets with detailed spectroscopy using JWST, owing to their extended atmospheres and small stars. However, the H2-dominated atmospheres that are consistent with habitable conditions cannot be too massive, and a moderate-sized H2-dominated atmosphere will lose mass to irradiation-driven atmospheric escape on rocky planets around M dwarfs. We evaluate volcanic outgassing and serpentinization as two potential ways to supply H2 and form a steady-state H2-dominated atmosphere. For rocky planets of 1–7 M ⊕ and early-, mid-, and late M-type dwarfs, the expected volcanic outgassing rates from a reduced mantle fall short of the escape rates by > ∼ 1 order of magnitude, and a generous upper limit of the serpentinization rate is still less than the escape rate by a factor of a few. Special mechanisms that may sustain the steady-state H2-dominated atmosphere include direct interaction between liquid water and mantle, heat-pipe volcanism from a reduced mantle, and hydrodynamic escape slowed down by efficient upper-atmospheric cooling. It is thus unlikely to find moderate-size, H2-dominated atmospheres on rocky planets of M dwarfs that would support habitable environments.
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Zhao-Jun, Ban, Zhang Jing-Lin, Wang Yong-Jiang, Yang Xiang-Zheng, Yuan Qiu-Ping, Xu Xiao-Juan, and Cai Hai-Ying. "Nutritional Quality of Red Dates (Zizyphus Jujube Mill.) in Response to Modified and Controlled Atmospheric Storage Conditions." Current Topics in Nutraceutical Research 18, no. 1 (June 24, 2018): 46–51. http://dx.doi.org/10.37290/ctnr2641-452x.18:46-51.
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Quality maintenance and ethanol metabolism of red date (Zizyphus jujube Mill.) fruits in response to modified atmosphere and controlled atmosphere (7% CO2, 3% O2 plus 90% N2) were investigated in the present study. Results showed that modified atmosphere and controlled atmosphere significantly maintained higher titratable and ascorbic acid contents during storage at 0°C for 32 days. In addition, ethanol accumulation and alcohol dehydrogenase activity indicated that ethanol metabolism in red dates was substantially inhibited by modified and controlled atmospheric storage conditions. Furthermore, the browning and polyphenoloxidase activity was also delayed by both atmospheric conditions compared with control. By evidence of sensory evaluation, results confirmed that both modified and controlled atmosphere packages contributed to the maintenance of better sweetness, sourness, firmness, juiciness and date flavor as well as overall preference after cold storage. Nonetheless, no significant difference on decay index of red dates was observed between changed atmospheres and untreated control after storage. Results from the present study are of importance to the red date industry on theoretical and practical aspects.
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Habib, Namrah, and Raymond T. Pierrehumbert. "Modeling Noncondensing Compositional Convection for Applications to Super-Earth and Sub-Neptune Atmospheres." Astrophysical Journal 961, no. 1 (January 1, 2024): 35. http://dx.doi.org/10.3847/1538-4357/ad04e2.
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Abstract Compositional convection is atmospheric mixing driven by density variations caused by compositional gradients. Previous studies have suggested that compositional gradients of atmospheric trace species within planetary atmospheres can impact convection and the final atmospheric temperature profile. In this work, we employ 3D convection-resolving simulations using Cloud Model 1 (CM1) to gain a fundamental understanding of how compositional variation influences convection and the final atmospheric state of exoplanet atmospheres. We perform 3D initial value problem simulations of noncondensing compositional convection for Earth-air, H2, and CO2 atmospheres. Conventionally, atmospheric convection is assumed to mix the atmosphere to a final, marginally stable state defined by a unique temperature profile. However, when there is compositional variation within an atmosphere, a continuous family of stable end states is possible, differing in the final state composition profile. Our CM1 simulations are used to determine which of the family of possible compositional end states is selected. Leveraging the results from our CM1 simulations, we develop a dry convective adjustment scheme for use in general circulation models (GCMs). This scheme relies on an energy analysis to determine the final adjusted atmospheric state. Our convection scheme produces results that agree with our CM1 simulations and can easily be implemented in GCMs to improve modeling of compositional convection in exoplanet atmospheres.
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Ohno, Kazumasa, and Jonathan J. Fortney. "Nitrogen as a Tracer of Giant Planet Formation. I. A Universal Deep Adiabatic Profile and Semianalytical Predictions of Disequilibrium Ammonia Abundances in Warm Exoplanetary Atmospheres." Astrophysical Journal 946, no. 1 (March 1, 2023): 18. http://dx.doi.org/10.3847/1538-4357/acafed.
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Abstract A major motivation of spectroscopic observations of giant exoplanets is to unveil planet formation processes from atmospheric compositions. Several recent studies suggested that atmospheric nitrogen, like carbon and oxygen, can provide important constraints on planetary formation environments. Since nitrogen chemistry can be far from thermochemical equilibrium in warm atmospheres, we extensively investigate under what conditions, and with what assumptions, the observable NH3 abundances can diagnose an atmosphere’s bulk nitrogen abundance. In the first paper of this series, we investigate atmospheric T–P profiles across equilibrium temperature, surface gravity, intrinsic temperature, atmospheric metallicity, and C/O ratio using a 1D radiative–convective equilibrium model. Models with the same intrinsic temperature and surface gravity coincide with a shared “universal” adiabat in the deep atmosphere, across a wide equilibrium temperature range (250–1200 K), which is not seen in hotter or cooler models. We explain this behavior in terms of the classic “radiative zero solution” and then establish a semianalytical T–P profile of the deep atmospheres of warm exoplanets. This profile is then used to predict vertically quenched NH3 abundances. At solar metallicity, our results show that the quenched NH3 abundance only coincides with the bulk nitrogen abundance (within 10%) at low intrinsic temperature, corresponding to a planet with a sub-Jupiter mass (≲1 M J) and old age (≳1 Gyr). If a planet has a high-metallicity (≳10× solar) atmosphere, the quenched NH3 abundance significantly underestimates the bulk nitrogen abundance at almost all planetary masses and ages. We suggest modeling and observational strategies to improve the assessment of bulk nitrogen from NH3.
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Watanabe, Yasuto, and Kazumi Ozaki. "Relative Abundances of CO2, CO, and CH4 in Atmospheres of Earth-like Lifeless Planets." Astrophysical Journal 961, no. 1 (January 1, 2024): 1. http://dx.doi.org/10.3847/1538-4357/ad10a2.
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Abstract Carbon is an essential element for life on Earth, and the relative abundances of major carbon species (CO2, CO, and CH4) in the atmosphere exert fundamental controls on planetary climate and biogeochemistry. Here we employed a theoretical model of atmospheric chemistry to investigate diversity in the atmospheric abundances of CO2, CO, and CH4 on Earth-like lifeless planets orbiting Sun-like (F-, G-, and K-type) stars. We focused on the conditions for the formation of a CO-rich atmosphere, which would be favorable for the origin of life. Results demonstrated that elevated atmospheric CO2 levels trigger photochemical instability of the CO budget in the atmosphere (i.e., CO runaway) owing to enhanced CO2 photolysis relative to H2O photolysis. Higher volcanic outgassing fluxes of reduced C (CO and CH4) also tend to initiate CO runaway. Our systematic examinations revealed that anoxic atmospheres of Earth-like lifeless planets could be classified in the phase space of CH4/CO2 versus CO/CO2, where a distinct gap in atmospheric carbon chemistry is expected to be observed. Our findings indicate that the gap structure is a general feature of Earth-like lifeless planets with reducing atmospheres orbiting Sun-like (F-, G-, and K-type) stars.
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Wunderlich, Fabian, Markus Scheucher, John Lee Grenfell, Franz Schreier, Clara Sousa-Silva, Mareike Godolt, and Heike Rauer. "Detectability of biosignatures on LHS 1140 b." Astronomy & Astrophysics 647 (March 2021): A48. http://dx.doi.org/10.1051/0004-6361/202039663.
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Context. Terrestrial extrasolar planets around low-mass stars are prime targets when searching for atmospheric biosignatures with current and near-future telescopes. The habitable-zone super-Earth LHS 1140 b could hold a hydrogen-dominated atmosphere, and is an excellent candidate for detecting atmospheric features. Aims. In this study we investigate how the instellation and planetary parameters influence the atmospheric climate, chemistry, and spectral appearance of LHS 1140 b. We study the detectability of selected molecules, in particular potential biosignatures, with the upcoming James Webb Space Telescope (JWST) and Extremely Large Telescope (ELT). Methods. In the first step we used the coupled climate–chemistry model 1D-TERRA to simulate a range of assumed atmospheric chemical compositions dominated by molecular hydrogen (H2) and carbon dioxide (CO2). In addition, we varied the concentrations of methane (CH4) by several orders of magnitude. In the second step we calculated transmission spectra of the simulated atmospheres and compared them to recent transit observations. Finally, we determined the observation time required to detect spectral bands with low-resolution spectroscopy using JWST, and the cross-correlation technique using ELT. Results. In H2-dominated and CH4-rich atmospheres oxygen (O2) has strong chemical sinks, leading to low concentrations of O2 and ozone (O3). The potential biosignatures ammonia (NH3), phosphine (PH3), chloromethane (CH3Cl), and nitrous oxide (N2O) are less sensitive to the concentration of H2, CO2, and CH4 in the atmosphere. In the simulated H2-dominated atmosphere the detection of these gases might be feasible within 20 to 100 observation hours with ELT or JWST when assuming weak extinction by hazes. Conclusions. If further observations of LHS 1140 b suggest a thin, clear, hydrogen-dominated atmosphere, the planet would be one of the best known targets to detect biosignature gases in the atmosphere of a habitable-zone rocky exoplanet with upcoming telescopes.
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Herbst, Konstantin, Saša Banjac, and Tom A. Nordheim. "Revisiting the cosmic-ray induced Venusian ionization with the Atmospheric Radiation Interaction Simulator (AtRIS)." Astronomy & Astrophysics 624 (April 2019): A124. http://dx.doi.org/10.1051/0004-6361/201935152.
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Context. Cosmic ray bombardment represents a major source of ionization in planetary atmospheres. The higher the energy of the primary cosmic ray particles, the deeper they can penetrate into the atmosphere. In addition, incident high energy cosmic ray particles induce extensive secondary particle cascades (“air showers”) that can contain up to several billion secondary particles per incoming primary particle. To quantify cosmic ray-induced effects on planetary atmospheres it is therefore important to accurately model the entire secondary particle cascade. This is particularly important in thick planetary atmospheres where the secondary particle cascades can develop extensively before being absorbed by the surface. Aims. Inside the Venusian atmosphere, cosmic rays are the dominant driver for the ionization below an altitude of ~100 km. In this work we revisit the numerical modeling of the galactic and solar cosmic-ray induced atmospheric ionization for cosmic ray ions from Hydrogen (Z = 1) to Nickel (Z = 28) and investigate the influence of strong solar energetic particle events inside the Venusian atmosphere. Methods. The Atmospheric Radiation Interaction Simulator (AtRIS), a newly developed simulation code to model the interaction of the near-(exo)planet particle and radiation field with the (exo)planetary atmosphere, was used to revisit the modeling of the altitude-dependent Venusian atmospheric ionization. Thereby, spherical geometry, the newest version of Geant4 (10.5) as well as the newest Geant4-based hadronic and electromagnetic interaction models were utilized. Results. Based on our new model approach we show that previous studies may have underestimated the galactic cosmic ray-induced atmospheric ion pair production by, amongst others, underestimating the influence of galactic cosmic ray protons above 1 TeV/nuc. Furthermore, we study the influence of 71 exceptionally strong solar particle events that were measured as Ground Level Enhancements at the Earth’s surface, and show a detailed analysis of the impact of such strong events on the Venusian ionization.
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Turner, Jennifer, Dominique Moran, and Yvonne Jewkes. "‘It's in the air here’: Atmosphere(s) of incarceration." Incarceration 3, no. 3 (August 3, 2022): 263266632211107. http://dx.doi.org/10.1177/26326663221110788.
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Contrary to descriptions of a desensitising situation – with restrictions on movement, monotonous regimes and sparse surroundings – much research highlights imprisonment as sensorially and emotionally powerful. Following work within the ‘turn to affect’ that focuses on non-verbal, non-conscious and, often, non-human embodied experiences, scholars have attended to how such elements cohere into ‘atmospheres’. Whilst the language of atmosphere is synonymous with the prison – a space that is widely anecdotally considered to conjure a particular ‘feeling’ – discussion of the mechanisms for and experiences of atmospheric production and consumption in this space has, thus far, evaded scholarly attention. Atmosphere is a word often used in prison literature, but it is rarely analytically unpacked. Accordingly, drawing on qualitative research data from individuals designing, and working and living in prisons, we focus on how various components – including aesthetics, olfaction, temperature, and the performances that arise from them – comprise sensory atmospheric affects in prison. In doing so, we find atmosphere(s) emerge – not simply from the materiality of the prison itself, but from cultural constructions of carceral and non-carceral landscapes and in conjunction with personal practice and preference. Accordingly, the prison is tied to particular constructions about what a prison should feel like and how people should (re)act to/in such spaces. In some cases, prison designers attempt to engineer particular atmospheres that cohere with wider political motivations around penal philosophies. However, despite the common reflection that prisons generate some kind of atmosphere, respondents are unable to offer a concrete description of what this may be, and much of our data highlights a definite precarity and changeability to atmospheric affect, which is likely to raise ambiguity around attempts to design carceral atmospheres.
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Smith, Durward, and Joseph D. Norton. "Reduced Atmosphere Storage of Chinese Chestnuts." HortScience 30, no. 4 (July 1995): 890A—890. http://dx.doi.org/10.21273/hortsci.30.4.890a.
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Stored Chinese chestnuts (Castanea molissima Blume) are extremely susceptible to spoilage by molds. This research was initiated to determine if storage at reduced atmospheres in conjunction with vacuum-infused mycostatic chemicals could reduce mold growth and enhance the quality of stored nuts. Nuts were treated with two levels of buffered sodium propionate and two levels of buffered sodium benzoate and stored either at atmospheric pressure or at 0.17 atmosphere (4.0% O2) and minimal gas circulation. Relative humidity was maintained at 88%. Mold counts, weight, texture, and moisture content were recorded every 20 days. Mold counts of the chemically treated nuts stored at atmospheric pressure did not differ from untreated nuts. Storage at reduced atmosphere in conjunction with chemical treatment inhibited mold growth, reduced weight loss, and preserved fresh quality and viability of the nuts.
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Kempton, Eliza M. R. "The properties of super-Earth atmospheres." Proceedings of the International Astronomical Union 6, S276 (October 2010): 212–17. http://dx.doi.org/10.1017/s1743921311020205.
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AbstractExtrasolar super-Earths likely have a far greater diversity in their atmospheric properties than giant planets. Super-Earths (planets with masses between 1 and 10 M⊕) lie in an intermediate mass regime between gas/ice giants like Neptune and rocky terrestrial planets like Earth and Venus. While some super-Earths (especially the more massive ones) may retain large amounts of hydrogen either from accretion processes or subsequent surface outgassing, other super-Earths should have atmospheres composed of predominantly heavier molecules, similar to the atmospheres of the rocky planets and moons of our Solar System. Others still may be entirely stripped of their atmospheres and remain as bare rocky cores. Of the two currently known transiting super-Earths one (GJ 1214b) likely falls into the former category with a thick atmosphere, while the other (CoRoT-7b) falls into the latter category with a very thin or nonexistent atmosphere. I review some of the theoretical work on super-Earth atmospheres, and I present methods for determining the bulk composition of a super-Earth atmosphere.
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Chance, Quadry, Sarah Ballard, and Keivan Stassun. "Signatures of Impact-driven Atmospheric Loss in Large Ensembles of Exoplanets." Astrophysical Journal 937, no. 1 (September 1, 2022): 39. http://dx.doi.org/10.3847/1538-4357/ac8a97.
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Abstract The results of large-scale exoplanet transit surveys indicate that the distribution of small planet radii is likely sculpted by atmospheric loss. Several possible physical mechanisms exist for this loss of primordial atmospheres, each of which produces a different set of observational signatures. In this study, we investigate the impact-driven mode of atmosphere loss via N-body simulations. We compare the results from giant impacts, at a demographic level, to results from another commonly invoked method of atmosphere loss, photoevaporation. Applying two different loss prescriptions to the same sets of planets, we then examine the resulting distributions of planets with retained primordial atmospheres. As a result of this comparison, we identify two new pathways toward discerning the dominant atmospheric-loss mechanism at work. Both of these pathways involve using transit multiplicity as a diagnostic, in examining the results of follow-up atmospheric and radial velocity surveys.
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Moses, Julianne I. "Chemical kinetics on extrasolar planets." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 372, no. 2014 (April 28, 2014): 20130073. http://dx.doi.org/10.1098/rsta.2013.0073.
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Chemical kinetics plays an important role in controlling the atmospheric composition of all planetary atmospheres, including those of extrasolar planets. For the hottest exoplanets, the composition can closely follow thermochemical-equilibrium predictions, at least in the visible and infrared photosphere at dayside (eclipse) conditions. However, for atmospheric temperatures , and in the uppermost atmosphere at any temperature, chemical kinetics matters. The two key mechanisms by which kinetic processes drive an exoplanet atmosphere out of equilibrium are photochemistry and transport-induced quenching. I review these disequilibrium processes in detail, discuss observational consequences and examine some of the current evidence for kinetic processes on extrasolar planets.
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Seidel, J. V., D. Ehrenreich, R. Allart, H. J. Hoeijmakers, C. Lovis, V. Bourrier, L. Pino, et al. "Into the storm: diving into the winds of the ultra-hot Jupiter WASP-76 b with HARPS and ESPRESSO." Astronomy & Astrophysics 653 (September 2021): A73. http://dx.doi.org/10.1051/0004-6361/202140569.
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Context. Despite swift progress in the characterisation of exoplanet atmospheres in composition and structure, the study of atmospheric dynamics has not progressed at the same speed. While theoretical models have been developed to describe the lower layers of the atmosphere, and independently, the exosphere, little is known about the intermediate layers up to the thermosphere. Aims. We aim to provide a clearer picture of atmospheric dynamics for the class of ultra-hot Jupiters, which are highly irradiated gas giants, based on the example of WASP-76 b. Methods. We jointly analysed two datasets that were obtained with the HARPS and ESPRESSO spectrographs to interpret the resolved planetary sodium doublet. We then applied the MERC code, which retrieves wind patterns, speeds, and temperature profiles on the line shape of the sodium doublet. An updated version of MERC, with added planetary rotation, also provides the possibility of modelling the latitude dependence of the wind patterns. Results. We retrieve the highest Bayesian evidence for an isothermal atmosphere, interpreted as a mean temperature of 3389 ± 227 K, a uniform day- to nightside wind of 5.5−2.0+1.4 km s−1 in the lower atmosphere with a vertical wind in the upper atmosphere of 22.7−4.1+4.9 km s−1, switching atmospheric wind patterns at 10−3 bar above the reference surface pressure (10 bar). Conclusions. Our results for WASP-76 b are compatible with previous studies of the lower atmospheric dynamics of WASP-76 b and other ultra-hot Jupiters. They highlight the need for vertical winds in the intermediate atmosphere above the layers probed by global circulation model studies to explain the line broadening of the sodium doublet in this planet. This work demonstrates the capability of exploiting the resolved spectral line shapes to observationally constrain possible wind patterns in exoplanet atmospheres. This is an invaluable input to more sophisticated 3D atmospheric models in the future.
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Johnstone, C. P., M. Güdel, H. Lammer, and K. G. Kislyakova. "Upper atmospheres of terrestrial planets: Carbon dioxide cooling and the Earth’s thermospheric evolution." Astronomy & Astrophysics 617 (September 2018): A107. http://dx.doi.org/10.1051/0004-6361/201832776.
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Context.The thermal and chemical structures of the upper atmospheres of planets crucially influence losses to space and must be understood to constrain the effects of losses on atmospheric evolution.Aims.We develop a 1D first-principles hydrodynamic atmosphere model that calculates atmospheric thermal and chemical structures for arbitrary planetary parameters, chemical compositions, and stellar inputs. We apply the model to study the reaction of the Earth’s upper atmosphere to large changes in the CO2abundance and to changes in the input solar XUV field due to the Sun’s activity evolution from 3 Gyr in the past to 2.5 Gyr in the future.Methods.For the thermal atmosphere structure, we considered heating from the absorption of stellar X-ray, UV, and IR radiation, heating from exothermic chemical reactions, electron heating from collisions with non-thermal photoelectrons, Joule heating, cooling from IR emission by several species, thermal conduction, and energy exchanges between the neutral, ion, and electron gases. For the chemical structure, we considered ~500 chemical reactions, including 56 photoreactions, eddy and molecular diffusion, and advection. In addition, we calculated the atmospheric structure by solving the hydrodynamic equations. To solve the equations in our model, we developed the Kompot code and have provided detailed descriptions of the numerical methods used in the appendices.Results.We verify our model by calculating the structures of the upper atmospheres of the modern Earth and Venus. By varying the CO2abundances at the lower boundary (65 km) of our Earth model, we show that the atmospheric thermal structure is significantly altered. Increasing the CO2abundances leads to massive reduction in thermospheric temperature, contraction of the atmosphere, and reductions in the ion densities indicating that CO2can significantly influence atmospheric erosion. Our models for the evolution of the Earth’s upper atmosphere indicate that the thermospheric structure has not changed significantly in the last 2 Gyr and is unlikely to change signficantly in the next few Gyr. The largest changes that we see take place between 3 and 2 Gyr ago, with even larger changes expected at even earlier times.
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Meerkötter, R., U. Schumann, D. R. Doelling, P. Minnis, T. Nakajima, and Y. Tsushima. "Radiative forcing by contrails." Annales Geophysicae 17, no. 8 (August 31, 1999): 1080–94. http://dx.doi.org/10.1007/s00585-999-1080-7.
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Abstract. A parametric study of the instantaneous radiative impact of contrails is presented using three different radiative transfer models for a series of model atmospheres and cloud parameters. Contrails are treated as geometrically and optically thin plane parallel homogeneous cirrus layers in a static atmosphere. The ice water content is varied as a function of ambient temperature. The model atmospheres include tropical, mid-latitude, and subarctic summer and winter atmospheres. Optically thin contrails cause a positive net forcing at top of the atmosphere. At the surface the radiative forcing is negative during daytime. The forcing increases with the optical depth and the amount of contrail cover. At the top of the atmosphere, a mean contrail cover of 0.1% with average optical depth of 0.2 to 0.5 causes about 0.01 to 0.03 Wm-2 daily mean instantaneous radiative forcing. Contrails cool the surface during the day and heat the surface during the night, and hence reduce the daily temperature amplitude. The net effect depends strongly on the daily variation of contrail cloud cover. The indirect radiative forcing due to particle changes in natural cirrus clouds may be of the same magnitude as the direct one due to additional cover.Key words. Atmospheric composition and structure (aerosols and particles) · Meteorology and atmospheric dynamics (climatology · radiative processes)
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Heng, Kevin. "The Transient Outgassed Atmosphere of 55 Cancri e." Astrophysical Journal Letters 956, no. 1 (October 1, 2023): L20. http://dx.doi.org/10.3847/2041-8213/acfe05.
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Abstract The enigmatic nature of 55 Cancri e has defied theoretical explanation. Any explanation needs to account for the observed variability of its secondary eclipse depth, which is at times consistent with zero in the visible/optical range of wavelengths—a phenomenon that does not occur with its also variable infrared eclipses. Yet despite this variability, its transit depth remains somewhat constant in time and is inconsistent with opaque material filling its Hill sphere. The current study explores the possibility of a thin, transient, secondary atmosphere on 55 Cancri e that is sourced by geochemical outgassing. Its transient nature derives from the inability of outgassing to be balanced by atmospheric escape. As the outgassed atmosphere escapes and is replenished, it rapidly adjusts to radiative equilibrium and the temperature fluctuations cause the infrared eclipse depths to vary. Atmospheres of pure carbon dioxide or carbon monoxide produce sufficient Rayleigh scattering to explain the observed optical/visible eclipse depths, which vanish in the absence of an atmosphere and the presence of a dark rocky surface. Atmospheres of pure methane are ruled out, because they produce insufficient Rayleigh scattering. Upcoming observations by the James Webb Space Telescope will potentially allow the atmospheric temperature and surface pressure, as well as the surface temperature, to be measured.
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Wade, G. A., L. Mashonkina, T. Ryabchikova, J. Krticka, J. Silvester, O. Kochukhov, J. C. Sousa, et al. "A 3-D look into the atmosphere?" Proceedings of the International Astronomical Union 5, H15 (November 2009): 151–60. http://dx.doi.org/10.1017/s1743921310008550.
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AbstractThe atmospheres of chemically peculiar stars can be highly structured in both the horizontal and vertical dimensions. While most prevalent in the magnetic stars, these structures can also exist in non-magnetic stars. In addition to providing an important window to understanding the physical processes at play in these complex atmospheres, they can also be exploited to study stellar pulsations. This article reviews contributions to the session “A 3D look into the atmosphere” of the Joint Discussion “Progress in understanding the physics of Ap and related stars”. It is divided into 3 sections: “Magnetic field and surface structures”, “Pulsations in the atmospheres of roAp stars/inversions”, and “Spectral synthesis/atmospheric models”.
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Madhusudhan, Nikku, Subhajit Sarkar, Savvas Constantinou, Måns Holmberg, Anjali A. A. Piette, and Julianne I. Moses. "Carbon-bearing Molecules in a Possible Hycean Atmosphere." Astrophysical Journal Letters 956, no. 1 (October 1, 2023): L13. http://dx.doi.org/10.3847/2041-8213/acf577.
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Abstract The search for habitable environments and biomarkers in exoplanetary atmospheres is the holy grail of exoplanet science. The detection of atmospheric signatures of habitable Earth-like exoplanets is challenging owing to their small planet–star size contrast and thin atmospheres with high mean molecular weight. Recently, a new class of habitable exoplanets, called Hycean worlds, has been proposed, defined as temperate ocean-covered worlds with H2-rich atmospheres. Their large sizes and extended atmospheres, compared to rocky planets of the same mass, make Hycean worlds significantly more accessible to atmospheric spectroscopy with JWST. Here we report a transmission spectrum of the candidate Hycean world K2-18 b, observed with the JWST NIRISS and NIRSpec instruments in the 0.9–5.2 μm range. The spectrum reveals strong detections of methane (CH4) and carbon dioxide (CO2) at 5σ and 3σ confidence, respectively, with high volume mixing ratios of ∼1% each in a H2-rich atmosphere. The abundant CH4 and CO2, along with the nondetection of ammonia (NH3), are consistent with chemical predictions for an ocean under a temperate H2-rich atmosphere on K2-18 b. The spectrum also suggests potential signs of dimethyl sulfide (DMS), which has been predicted to be an observable biomarker in Hycean worlds, motivating considerations of possible biological activity on the planet. The detection of CH4 resolves the long-standing missing methane problem for temperate exoplanets and the degeneracy in the atmospheric composition of K2-18 b from previous observations. We discuss possible implications of the findings, open questions, and future observations to explore this new regime in the search for life elsewhere.
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Krissansen-Totton, Joshua. "Implications of Atmospheric Nondetections for Trappist-1 Inner Planets on Atmospheric Retention Prospects for Outer Planets." Astrophysical Journal Letters 951, no. 2 (July 1, 2023): L39. http://dx.doi.org/10.3847/2041-8213/acdc26.
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Abstract JWST secondary eclipse observations of Trappist-1b seemingly disfavor atmospheres >∼1 bar since heat redistribution is expected to yield dayside emission temperature below the ∼500 K observed. Given the similar densities of Trappist-1 planets, and the theoretical potential for atmospheric erosion around late M dwarfs, this observation might be assumed to imply substantial atmospheres are also unlikely for the outer planets. However, the processes governing atmosphere erosion and replenishment are fundamentally different for inner and outer planets. Here, an atmosphere–interior evolution model is used to show that an airless Trappist-1b (and c) only weakly constrains stellar evolution, and that the odds of outer planets e and f retaining substantial atmospheres remain largely unchanged. This is true even if the initial volatile inventories of planets in the Trappist-1 system are highly correlated. The reason for this result is that b and c sit unambiguously interior to the runaway greenhouse limit, and so have potentially experienced ∼8 Gyr of X-ray and extreme ultraviolet–driven hydrodynamic escape; complete atmospheric erosion in this environment only weakly constrains stellar evolution and escape parameterizations. In contrast, e and f reside within the habitable zone, and likely experienced a comparatively short steam atmosphere during Trappist-1's pre-main sequence, and consequently complete atmospheric erosion remains unlikely across a broad swath of parameter space (e and f retain atmospheres in ∼98% of model runs). Naturally, it is still possible that all Trappist-1 planets formed volatile-poor and are all airless today. But the airlessness of b (and c) does not require this, and as such, JWST transit spectroscopy of e and f remains the best near-term opportunity to characterize the atmospheres of habitable zone terrestrial planets.
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Olsen, K. S., A. Trokhimovskiy, A. S. Braude, O. I. Korablev, A. A. Fedorova, C. F. Wilson, M. R. Patel, et al. "Upper limits for phosphine (PH3) in the atmosphere of Mars." Astronomy & Astrophysics 649 (April 30, 2021): L1. http://dx.doi.org/10.1051/0004-6361/202140868.
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Phosphine (PH3) is proposed to be a possible biomarker in planetary atmospheres and has been claimed to have been observed in the atmosphere of Venus, sparking interest in the habitability of Venus’s atmosphere. Observations of another biomarker, methane (CH4), have been reported several times in the atmosphere of Mars, hinting at the possibility of a past or present biosphere. The Atmospheric Chemistry Suite on the ExoMars Trace Gas Orbiter has a spectral range that includes several absorption lines of PH3 with line strengths comparable to previously observed CH4 lines. The signature of PH3 was not observed in the 192 observations made over a full Martian year of observations, and here we report upper limits of 0.1–0.6 ppbv.
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Wogan, Nicholas F., David C. Catling, Kevin J. Zahnle, and Roxana Lupu. "Origin-of-life Molecules in the Atmosphere after Big Impacts on the Early Earth." Planetary Science Journal 4, no. 9 (September 1, 2023): 169. http://dx.doi.org/10.3847/psj/aced83.
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Abstract The origin of life on Earth would benefit from a prebiotic atmosphere that produced nitriles, like HCN, which enable ribonucleotide synthesis. However, geochemical evidence suggests that Hadean air was relatively oxidizing with negligible photochemical production of prebiotic molecules. These paradoxes are resolved by iron-rich asteroid impacts that transiently reduced the entire atmosphere, allowing nitriles to form in subsequent photochemistry. Here we investigate impact-generated reducing atmospheres using new time-dependent, coupled atmospheric chemistry and climate models that account for gas-phase reactions and surface catalysis. The resulting H2-, CH4-, and NH3-rich atmospheres persist for millions of years, until the hydrogen escapes to space. The HCN and HCCCN production and rainout to the surface can reach 109 molecules cm−2 s−1 in hazy atmospheres with a mole ratio of CH4/CO2 > 0.1. Smaller CH4/CO2 ratios produce HCN rainout rates of <105 molecules cm−2 s−1 and negligible HCCCN. The minimum impactor mass that creates atmospheric CH4/CO2 > 0.1 is 4 × 1020–5 × 1021 kg (570–1330 km diameter), depending on how efficiently iron reacts with a steam atmosphere, the extent of atmospheric equilibration with an impact-induced melt pond, and the surface area of nickel that catalyzes CH4 production. Alternatively, if steam permeates and deeply oxidizes the crust, impactors of ∼1020 kg could be effective. Atmospheres with copious nitriles have >360 K surface temperatures, perhaps posing a challenge for RNA longevity, although cloud albedo can produce cooler climates. Regardless, postimpact cyanide can be stockpiled and used in prebiotic schemes after hydrogen has escaped to space.
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Claudi, R., M. S. Erculiani, G. Galletta, D. Billi, E. Pace, D. Schierano, E. Giro, and M. D'Alessandro. "Simulating super earth atmospheres in the laboratory." International Journal of Astrobiology 15, no. 1 (May 20, 2015): 35–44. http://dx.doi.org/10.1017/s1473550415000117.
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AbstractSeveral space missions, such as JWST, TESS and the very recently proposed ARIEL, or ground-based experiments, as SPHERE and GPI, have been proposed to measure the atmospheric transmission, reflection and emission spectra of extrasolar planets. The planet atmosphere characteristics and possible biosignatures will be inferred by studying planetary spectra in order to identify the emission/absorption lines/bands from atmospheric molecules such as water (H2O), carbon monoxide (CO), methane (CH4), ammonia (NH3), etc. In particular, it is important to know in detail the optical characteristics of gases in the typical physical conditions of the planetary atmospheres and how these characteristics could be affected by radiation driven photochemical and biochemical reaction. The main aim of the project ‘Atmosphere in a Test Tube’ is to provide insights on exoplanet atmosphere modification due to biological intervention. This can be achieved simulating planetary atmosphere at different pressure and temperature conditions under the effects of radiation sources, used as proxies of different bands of the stellar emission. We are tackling the characterization of extrasolar planet atmospheres by mean of innovative laboratory experiments described in this paper. The experiments are intended to reproduce the conditions on warm earths and super earths hosted by low-mass M dwarfs primaries with the aim to understand if a cyanobacteria population hosted on a Earth-like planet orbiting an M0 star is able to maintain its photosynthetic activity and produce traceable signatures.
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Kurosaki, Kenji, Yasunori Hori, Masahiro Ogihara, and Masanobu Kunitomo. "Evolution of a Water-rich Atmosphere Formed by a Giant Impact on an Earth-sized Planet." Astrophysical Journal 957, no. 2 (October 31, 2023): 67. http://dx.doi.org/10.3847/1538-4357/acfe0a.
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Abstract The atmosphere of a terrestrial planet that is replenished with secondary gases should have accumulated hydrogen-rich gas from its protoplanetary disk. Although a giant impact blows off a large fraction of the primordial atmosphere of a terrestrial planet in the late formation stage, the remaining atmosphere can become water-rich via chemical reactions between hydrogen and vaporized core material. We find that a water-rich postimpact atmosphere forms when a basaltic or CI chondrite core is assumed. In contrast, little postimpact water is generated for an enstatite chondrite core. We investigate the X-ray- and UV-driven mass loss from an Earth-mass planet with an impact-induced multicomponent H2–He–H2O atmosphere for Gyr. We show that water is left in the atmosphere of an Earth-mass planet when the low flux of escaping hydrogen cannot drag water upward via collisions. For a water-dominated atmosphere to form, the atmospheric mass fraction of an Earth-mass planet with an oxidizing core after a giant impact must be less than a few times 0.1%. We also find that Earth-mass planets with water-dominated atmospheres can exist at semimajor axes ranging from a few times 0.1 au to a few au around a Sun-like star, depending on the mass-loss efficiency. Such planets are important targets for atmospheric characterization in the era of JWST. Our results indicate that efficient mixing between hydrogen and rocky components during giant impacts can play a role in the production of water in an Earth-mass planet.
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Loubeau, Alexandra, Victor W. Sparrow, William Doebler, Sriram K. Rallabhandi, Stephane Lemaire, Pierre-Elie Normand, and Sandy R. Liu. "New reference day atmosphere for analyses of quiet supersonic overflight." Journal of the Acoustical Society of America 154, no. 4_supplement (October 1, 2023): A106. http://dx.doi.org/10.1121/10.0022945.
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New reference day atmospheric conditions have been defined for future supersonic aircraft en route noise certification procedures. As field measurements are acquired, in a variety of atmospheric conditions, it is important to relate those measurements back to a common reference atmosphere to provide uniformity in method across applicants for noise certification. Because of the long propagation distances involved between the aircraft flight altitude and the ground, en route noise certification measurements can be substantially affected by the atmosphere. Properties, such as pressure, density, temperature, humidity, and winds, vary with altitude. Therefore, the definition of reference atmospheric profiles as a function of altitude are needed instead of the coarse layered atmosphere and homogeneous humidity used in subsonic aircraft landing and takeoff noise certification. Ground loudness levels from overflight of a quiet supersonic demonstrator concept, calculated with atmospheric data from sites across the world, were compared with the results from several candidate reference atmospheres to identify a reference that would minimize the required adjustment to certification test measurements. The existing ICAO 7488/3 profiles for temperature and pressure, combined with a modified ISO 5878 humidity profile, were found to offer the best results.
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Katyal, Nisha, Gianluigi Ortenzi, John Lee Grenfell, Lena Noack, Frank Sohl, Mareike Godolt, Antonio García Muñoz, Franz Schreier, Fabian Wunderlich, and Heike Rauer. "Effect of mantle oxidation state and escape upon the evolution of Earth’s magma ocean atmosphere." Astronomy & Astrophysics 643 (November 2020): A81. http://dx.doi.org/10.1051/0004-6361/202038779.
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Context. The magma ocean period was a critical phase determining how Earth’s atmosphere developed into habitability. However, there are major uncertainties in the role of key processes such as outgassing from the planetary interior and escape of species to space that play a major role in determining the atmosphere of early Earth. Aims. We investigate the effect of outgassing of various species and escape of H2 for different mantle redox states upon the composition and evolution of the atmosphere for the magma ocean period. Methods. We included an important new atmosphere-interior coupling mechanism: the redox evolution of the mantle, which strongly affects the outgassing of species. We simulated the volatile outgassing and chemical speciation at the surface for various redox states of the mantle by employing a C-H-O based chemical speciation model combined with an interior outgassing model. We then applied a line-by-line radiative transfer model to study the remote appearance of the planet in terms of the infrared emission and transmission. Finally, we used a parameterized diffusion-limited and XUV energy-driven atmospheric escape model to calculate the loss of H2 to space. Results. We have simulated the thermal emission and transmission spectra for reduced and oxidized atmospheres present during the magma ocean period of Earth. Reduced/thin atmospheres consisting of H2 in abundance emit more radiation to space and have a larger effective height than oxidized/thick atmospheres, which are abundant in H2O and CO2. We obtain that the outgassing rates of H2 from the mantle into the atmosphere are a factor of ten times higher than the rates of diffusion-limited escape to space. We estimate the timescale of total mass loss of outgassed H2 via escape to be few tens of million years, which is comparable to other studies. Conclusions. Our work presents useful insight into the development of the terrestrial atmosphere during the magma ocean period and provides input to guide future studies that discuss exoplanetary interior compositions and their possible links with atmospheric compositions that might be estimated from observed infrared spectra by future missions.
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Kushtin, V. I., and A. N. Ivanov. "Determination of adjusted range corrections measured by electro-optical systems." Journal of Physics: Conference Series 2131, no. 2 (December 1, 2021): 022048. http://dx.doi.org/10.1088/1742-6596/2131/2/022048.
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Abstract Electromagnetic radiation used to determine ranges passes through media with different characteristics that affect the electromagnetic waves propagation speed and, accordingly, the accuracy of distance determination. The problem of the radio signal delay due to the influence of the atmosphere is an urgent problem, the solution of which is currently limited mainly to the calculation of range corrections using various atmospheric models. Depending on the required accuracy, the length of the measured line, the range of zenith distances, the availability of information about the state of the atmosphere, a flat, spherical, ellipsoidal model of atmospheres is used to determine the range corrections. In view of the fact that the parameters of the atmosphere characterizing its state along the electromagnetic wave path at the time of measurement, as a rule, are unknown, it becomes necessary to apply one or another hypothesis about the distribution of atmospheric parameters with height. In this paper, we propose a solution to the problem of determining corrections to the measured ranges from the known parameters of the atmosphere only at the initial and final points of the electromagnetic waves’ trajectory.
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Hicks, Stephen. "“The feel of the place”: Investigating atmosphere with the residents of a modernist housing estate." Qualitative Social Work 19, no. 3 (May 2020): 460–80. http://dx.doi.org/10.1177/1473325020911672.
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Atmosphere is a neglected topic in social work, and so this article considers the production of atmospheres amongst the residents of an extant 1960s housing scheme in Edinburgh (UK). This is in order to address not only the complexity of feelings about living on such an estate but also to consider what consequences the paying of attention to atmosphere’s production and effects might have for a social work concern with welfare and wellbeing. The article is based upon semi-structured and walking interviews with 17 residents – council or private renters and home-owners – of Claremont Court, a mixed, low-rise estate and analyses their description and crafting of atmosphere as a way to understand questions of belonging, welfare and community in situ. After reviewing some existing research on atmosphere and outlining methodological issues relating to the Claremont Court project, the article goes on to consider how residents described their feelings about or sense of the estate and its design before discussing the emergence of contradictory narratives about home. The production of narratives about those needing welfare support is particularly pertinent to atmospheric accounts of the housing scheme, and so the article addresses this before finally making an argument for the relevance of immersive and emplaced accounts of space and place for both social work practice and research.
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Itcovitz, Jonathan P., Auriol S. P. Rae, Robert I. Citron, Sarah T. Stewart, Catriona A. Sinclair, Paul B. Rimmer, and Oliver Shorttle. "Reduced Atmospheres of Post-impact Worlds: The Early Earth." Planetary Science Journal 3, no. 5 (May 1, 2022): 115. http://dx.doi.org/10.3847/psj/ac67a9.
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Abstract Impacts may have had a significant effect on the atmospheric chemistry of the early Earth. Reduced phases in the impactor (e.g., metallic iron) can reduce the planet’s H2O inventory to produce massive atmospheres rich in H2. While previous studies have focused on the interactions between the impactor and atmosphere in such scenarios, we investigate two further effects: (1) the distribution of the impactor’s iron inventory during impact between the target interior, target atmosphere, and escaping the target; and (2) interactions between the post-impact atmosphere and the impact-generated melt phase. We find that these two effects can potentially counterbalance each other, with the melt–atmosphere interactions acting to restore reducing power to the atmosphere that was initially accreted by the melt phase. For a ∼1022 kg impactor, when the iron accreted by the melt phase is fully available to reduce this melt, we find an equilibrium atmosphere with H2 column density ∼104 moles cm−2 (pH2 ∼ 120 bars, X H2 ∼ 0.77), consistent with previous estimates. However, when the iron is not available to reduce the melt (e.g., sinking out in large diameter blobs), we find significantly less H2 (7 × 102 − 5 × 103 moles cm−2, pH2 ≲ 60 bars, X H2 ≲ 0.41). These lower H2 abundances are sufficiently high that species important to prebiotic chemistry can form (e.g., NH3, HCN), but sufficiently low that the greenhouse heating effects associated with highly reducing atmospheres, which are problematic to such chemistry, are suppressed. The manner in which iron is accreted by the impact-generated melt phase is critical in determining the reducing power of the atmosphere and resolidified melt pool in the aftermath of impact.
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Hands, Tom O., and R. Helled. "Super stellar abundances of alkali metals suggest significant migration for hot Jupiters." Monthly Notices of the Royal Astronomical Society 509, no. 1 (October 18, 2021): 894–902. http://dx.doi.org/10.1093/mnras/stab2967.
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ABSTRACT We investigate the origin of the measured overabundance of alkali metals in the atmospheres of hot gas giants, relative to both their host stars and their atmospheric water abundances. We show that formation exterior to the water snow line followed by inward disc-driven migration results in excess accretion of oxygen-poor, refractory-rich material from within the snow-line. This naturally leads to enrichment of alkali metals in the planetary atmosphere relative to the bulk composition of its host star but relative abundances of water that are similar to the stellar host. These relative abundances cannot be explained by in situ formation which places the refractory elements in the planetary deep interior rather than the atmosphere. We therefore suggest that the measured compositions of the atmospheres of hot Jupiters are consistent with significant migration for at least a subset of hot gas giants. Our model makes robust predictions about atmospheric composition that can be confirmed with future data from JWST and Ariel.
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Flagg, Laura, Jake D. Turner, Emily Deibert, Andrew Ridden-Harper, Ernst de Mooij, Ryan J. MacDonald, Ray Jayawardhana, Neale Gibson, Adam Langeveld, and David Sing. "ExoGemS Detection of a Metal Hydride in an Exoplanet Atmosphere at High Spectral Resolution." Astrophysical Journal Letters 953, no. 2 (August 1, 2023): L19. http://dx.doi.org/10.3847/2041-8213/ace529.
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Abstract Exoplanet atmosphere studies are often enriched by synergies with brown dwarf analogs. However, many key molecules commonly seen in brown dwarfs have yet to be confirmed in exoplanet atmospheres. An important example is chromium hydride (CrH), which is often used to probe atmospheric temperatures and classify brown dwarfs into spectral types. Recently, tentative evidence for CrH was reported in the low-resolution transmission spectrum of the hot Jupiter WASP-31b. Here, we presenthigh spectral resolution observations of WASP-31b’s transmission spectrum from GRACES/Gemini North and UVES/Very Large Telescope. We detect CrH at 5.6σ confidence, representing the first metal hydride detection in an exoplanet atmosphere at high spectral resolution. Our findings constitute a critical step in understanding the role of metal hydrides in exoplanet atmospheres.
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Paton, M. D., A. M. Harri, T. Mäkinen, and H. Savijärvi. "Martian atmospheric model with a high-fidelity subsurface thermal scheme." Geoscientific Instrumentation, Methods and Data Systems Discussions 2, no. 2 (September 11, 2012): 737–63. http://dx.doi.org/10.5194/gid-2-737-2012.
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Abstract. As the Martian atmosphere is observed in ever greater detail, more realistic computer models are required to interpret these measurements. Physical exchange processes between the atmosphere's lower boundary and the surface are often simplified. This is because the atmospheric calculations can describe the behaviour of the atmosphere accurately in many cases and simplifying the boundaries saves computing resources. However, the vertical heterogeneity of the subsurface (such as the presence of dust and ice layers) will interact via heat and mass transfer with the atmosphere. Here a new realistic thermal scheme is introduced for use with a 1-D atmospheric column model useful for investigating the subsurface for layered material and to provide more accurate modelling of the Martian atmosphere. The model with the updated scheme produces results that are identical to the previous versions of the model in identical (non-layered) conditions. The updated model fits well to Viking 1 temperature data from the atmosphere using realistic thermal parameters. Introducing layered material, with different thermal properties, produces noticeable changes in the maximum and diurnal temperatures when changing the thickness of its top layer. The time of maximum surface temperature is only significantly changed when the thickness of the top layer is a moderate fraction of the top layer's skin depth.
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Paton, M. D., A. M. Harri, T. Mäkinen, and H. Savijärvi. "High-fidelity subsurface thermal model as part of a Martian atmospheric column model." Geoscientific Instrumentation, Methods and Data Systems 2, no. 1 (January 18, 2013): 17–27. http://dx.doi.org/10.5194/gi-2-17-2013.
Full textAbstract:
Abstract. As the Martian atmosphere is observed in ever greater detail, more realistic computer models are required to interpret these measurements. Physical exchange processes between the atmosphere's lower boundary and the surface are often simplified. This is because the atmospheric calculations can describe the behaviour of the atmosphere accurately in many cases and simplifying the boundaries saves computing resources. However, the vertical heterogeneity of the subsurface (such as the presence of dust and ice layers) will interact via heat and mass transfer with the atmosphere. Here a new realistic numerical thermal conductivity scheme is introduced for use with a 1-D atmospheric column model useful for investigating the subsurface for layered material and to provide more accurate modelling of the Martian atmosphere. The model with the updated scheme produces results that are identical to the previous versions of the model in identical (non-layered) conditions. The updated model fits well to Viking 1 temperature data from the atmosphere using realistic thermal parameters. Introducing layered material, with different thermal properties, produces noticeable changes in the maximum and diurnal temperatures when changing the thickness of its top layer. The time of maximum surface temperature is only significantly changed when the thickness of the top layer is a moderate fraction of the top layer's skin depth.
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Zhang, Xi, Cheng Li, Huazhi Ge, and Tianhao Le. "The Inhomogeneity Effect. III. Weather Impacts on the Heat Flow of Hot Jupiters." Astrophysical Journal 957, no. 1 (October 23, 2023): 22. http://dx.doi.org/10.3847/1538-4357/acee7d.
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Abstract The interior flux of a giant planet impacts atmospheric motion, and the atmosphere dictates the interior’s cooling. Here we use a non-hydrostatic general circulation model (Simulating Non-hydrostatic Atmospheres on Planets) coupled with a multi-stream multi-scattering radiative module (High-performance Atmospheric Radiation Package) to simulate the weather impacts on the heat flow of hot Jupiters. We found that the vertical heat flux is primarily transported by convection in the lower atmosphere and regulated by dynamics and radiation in the overlying radiation-circulation zone. The temperature inversion occurs on the dayside and reduces the upward radiative flux. The atmospheric dynamics relay the vertical heat transport until the radiation becomes efficient in the upper atmosphere. The cooling flux increases with atmospheric drag due to increased day–night contrast and spatial inhomogeneity. The temperature dependence of the infrared opacity greatly amplifies the opacity inhomogeneity. Although atmospheric circulation could transport heat downward in a narrow region above the radiative-convective boundary, the opacity inhomogeneity effect overcomes the dynamical effect and leads to a larger overall interior cooling than the local simulations with the same interior entropy and stellar flux. The enhancement depends critically on the equilibrium temperature, drag, and atmospheric opacity. In a strong-drag atmosphere hotter than 1600 K, a significant inhomogeneity effect in three-dimensional (3D) models can boost interior cooling several-fold compared to the 1D radiative-convective equilibrium models. This study confirms the analytical argument of the inhomogeneity effect in the companion papers by Zhang. It highlights the importance of using 3D atmospheric models in understanding the inflation mechanisms of hot Jupiters and giant planet evolution in general.
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Ridden-Harper, Andrew, Stevanus K. Nugroho, Laura Flagg, Ray Jayawardhana, Jake D. Turner, Ernst de Mooij, Ryan MacDonald, et al. "High-resolution Transmission Spectroscopy of the Terrestrial Exoplanet GJ 486b." Astronomical Journal 165, no. 4 (March 21, 2023): 170. http://dx.doi.org/10.3847/1538-3881/acbd39.
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Abstract Terrestrial exoplanets orbiting M-dwarf stars are promising targets for transmission spectroscopy with existing or near-future instrumentation. The atmospheric composition of such rocky planets remains an open question, especially given the high X-ray and ultraviolet flux from their host M dwarfs that can drive atmospheric escape. The 1.3 R ⊕ exoplanet GJ 486b (T eq ∼ 700 K), orbiting an M3.5 star, is expected to have one of the strongest transmission spectroscopy signals among known terrestrial exoplanets. We observed three transits of GJ 486b using three different high-resolution spectrographs: IRD on Subaru, IGRINS on Gemini-South, and SPIRou on the Canada–France–Hawai’i Telescope. We searched for atmospheric absorption from a wide variety of molecular species via the cross-correlation method, but did not detect any robust atmospheric signals. Nevertheless, our observations are sufficiently sensitive to rule out several clear atmospheric scenarios via injection and recovery tests, and extend comparative exoplanetology into the terrestrial regime. Our results suggest that GJ 486b does not possess a clear H2/He-dominated atmosphere, nor a clear 100% water-vapor atmosphere. Other secondary atmospheres with high mean molecular weights or H2/He-dominated atmospheres with clouds remain possible. Our findings provide further evidence suggesting that terrestrial planets orbiting M-dwarf stars may experience significant atmospheric loss.
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Nayak, Saurabh, and Priyanka Dubey. "Machine Learning Methods to Weather Forecasting to Predict Apparent Temperature: A Review." International Journal for Research in Applied Science and Engineering Technology 11, no. 1 (January 31, 2023): 958–61. http://dx.doi.org/10.22214/ijraset.2023.48718.
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bstract: Predicting the atmosphere's state for a future date and specific place is the problem of weather forecasting. Traditionally, the atmosphere has been treated as a fluid in physical simulations to accomplish this. The equations for fluid dynamics and thermodynamics are numerically solved to determine the current state of the atmosphere and its future state. However, the system of ordinary differential equations that governs this physical model is unstable under perturbations, uncertainties in the initial measurements of the atmospheric conditions, and a lack of understanding of complex atmospheric processes govern the range of accurate weather forecasting to a 10 day period, beyond which weather forecasts are significantly unreliable. Contrarily, machine learning doesn't need a thorough understanding of the physical processes that govern the atmosphere and is more resilient to perturbations. As a result, machine learning could be a good substitute for physical models in weather forecasting
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Padjaroen, T., S. Awiphan, and S. Komonjinda. "Transmission spectroscopy analyses of Jovian planets with Hubble Space Telescope." Journal of Physics: Conference Series 2653, no. 1 (December 1, 2023): 012025. http://dx.doi.org/10.1088/1742-6596/2653/1/012025.
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Abstract Studying the chemical compositions of exoplanetary atmospheres provides valuable information about the conditions and characteristics of those atmospheres, which could help search for signs of extraterrestrial life. To date, over 3,000 exoplanets have been discovered using the transit method. The transmission spectroscopy technique, which studies exoplanetary atmospheres during their transits, is widely used to study the atmosphere of transiting exoplanets. Wide Field Camera 3 (WFC3), an instrument on the Hubble Space Telescope (HST), use the transmission spectroscopy technique by observing the spectrum of light curves of transiting exoplanets in optical and infrared wavelengths, which could reveal some molecular absorption in the exoplanetary atmosphere. In this work, we study the atmospheres of 20 transiting exoplanets that are Jovian planets. Light curves of these exoplanets observed by the WFC3 are used to analyze their physical properties using the Iraclis package and transit depth using the TransitFit package, a python exoplanetary fitting package based on nested sampling algorithms. Our physical parameters from TransitFit are approximately the same as those in previous literature. Finally, TauREx 3, a fully Bayesian spectral retrieval code, analyzes the transit depth per wavelength channel and reveals atmospheric compositions of these exoplanetary atmospheres. One notable finding from our analysis is the detection of 5 − 3 + 8 % H2O abundance in the atmosphere of WASP-63 b.
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Nakayama, Akifumi, Masahiro Ikoma, and Naoki Terada. "Survival of Terrestrial N2–O2 Atmospheres in Violent XUV Environments through Efficient Atomic Line Radiative Cooling." Astrophysical Journal 937, no. 2 (September 29, 2022): 72. http://dx.doi.org/10.3847/1538-4357/ac86ca.
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Abstract Atmospheres play a crucial role in planetary habitability. Around M dwarfs and young Sun-like stars, planets receiving the same insolation as the present-day Earth are exposed to intense stellar X-rays and extreme-ultraviolet (XUV) radiation. This study explores the fundamental question of whether the atmosphere of present-day Earth could survive in such harsh XUV environments. Previous theoretical studies suggest that stellar XUV irradiation is sufficiently intense to remove such atmospheres completely on short timescales. In this study, we develop a new upper-atmospheric model and re-examine the thermal and hydrodynamic responses of the thermospheric structure of an Earth-like N2–O2 atmosphere, on an Earth-mass planet, to an increase in the XUV irradiation. Our model includes the effects of radiative cooling via electronic transitions of atoms and ions, known as atomic line cooling, in addition to the processes accounted for by previous models. We demonstrate that atomic line cooling dominates over the hydrodynamic effect at XUV irradiation levels greater than several times the present level of the Earth. Consequentially, the atmosphere’s structure is kept almost hydrostatic, and its escape remains sluggish even at XUV irradiation levels up to a thousand times that of the Earth at present. Our estimates for the Jeans escape rates of N2–O2 atmospheres suggest that these 1 bar atmospheres survive in early active phases of Sun-like stars. Even around active late M dwarfs, N2–O2 atmospheres could escape significant thermal loss on timescales of gigayears. These results give new insights into the habitability of terrestrial exoplanets and the Earth’s climate history.
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Ih, Jegug, Eliza M. R. Kempton, Emily A. Whittaker, and Madeline Lessard. "Constraining the Thickness of TRAPPIST-1 b’s Atmosphere from Its JWST Secondary Eclipse Observation at 15 μm." Astrophysical Journal Letters 952, no. 1 (July 1, 2023): L4. http://dx.doi.org/10.3847/2041-8213/ace03b.
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Abstract Recently, the first JWST measurement of thermal emission from a rocky exoplanet was reported. The inferred dayside brightness temperature of TRAPPIST-1 b at 15 μm is consistent with the planet having no atmosphere and therefore no mechanism by which to circulate heat to its nightside. In this Letter, we compare TRAPPIST-1 b's measured secondary eclipse depth to predictions from a suite of self-consistent radiative-convective equilibrium models in order to quantify the maximum atmospheric thickness consistent with the observation. We find that plausible atmospheres (i.e., those that contain at least 100 ppm CO2) with surface pressures greater than 0.3 bar are ruled out at 3σ, regardless of the choice of background atmosphere, and a Mars-like thin atmosphere with surface pressure 6.5 mbar composed entirely of CO2 is also ruled out at 3σ. Thicker atmospheres of up to 10 bar (100 bar) are consistent with the data at 1σ (3σ) only if the atmosphere lacks any strong absorbers across the mid-IR wavelength range—a scenario that we deem unlikely. We additionally model the emission spectra for bare-rock planets of various compositions. We find that a basaltic, metal-rich, and Fe-oxidized surface best matches the measured eclipse depth to within 1σ, and the best-fit gray albedo is 0.02 ± 0.11. We conclude that planned secondary eclipse observations at 12.8 μm will serve to validate TRAPPIST-1 b's high observed brightness temperature, but are unlikely to further distinguish among the consistent atmospheric and bare-rock scenarios.
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Radmilović-Radjenović, Marija, Martin Sabo, and Branislav Radjenović. "Transport Characteristics of the Electrification and Lightning of the Gas Mixture Representing the Atmospheres of the Solar System Planets." Atmosphere 12, no. 4 (March 29, 2021): 438. http://dx.doi.org/10.3390/atmos12040438.
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Electrification represents a fundamental process in planetary atmospheres, widespread in the Solar System. The atmospheres of the terrestrial planets (Venus, Earth, and Mars) range from thin to thick are rich in heavier gases and gaseous compounds, such as carbon dioxide, nitrogen, oxygen, argon, sodium, sulfur dioxide, and carbon monoxide. The Jovian planets (Jupiter, Saturn, Uranus, and Neptune) have thick atmospheres mainly composed of hydrogen and helium involving. The electrical discharge processes occur in the planetary atmospheres leading to potential hazards due to arcing on landers and rovers. Lightning does not only affect the atmospheric chemical composition but also has been involved in the origin of life in the terrestrial atmosphere. This paper is dealing with the transport parameters and the breakdown voltage curves of the gas compositions representing atmospheres of the planets of the Solar System. Ionization coefficients, electron energy distribution functions, and the mean energy of the atmospheric gas mixtures have been calculated by BOLSIG+. Transport parameters of the carbon dioxide rich atmospheric compositions are similar but differ from those of the Earth’s atmosphere. Small differences between parameters of the Solar System’s outer planets can be explained by a small abundance of their constituent gases as compared to the abundance of hydrogen. Based on the fit of the reduced effective ionization coefficient, the breakdown voltage curves for atmospheric mixtures have been plotted. It was found that the breakdown voltage curves corresponding to the atmospheres of Solar System planets follow the standard scaling law. Results of calculations satisfactorily agree with the available data from the literature. The minimal and the maximal value of the voltage required to trigger electric breakdown is obtained for the Martian and Jupiter atmospheres, respectively.