PS5.2 | Observations and Modeling of Planets within the Solar System and Beyond
EDI
Observations and Modeling of Planets within the Solar System and Beyond
Convener: Maggie Thompson | Co-conveners: Daniel Williams, Emeline Bolmont, Fabian Seidler, Neil Lewis, Elsa Ducrot, Aurélien Falco
Orals
| Tue, 16 Apr, 08:30–10:10 (CEST)
 
Room 1.31/32, Tue, 16 Apr, 16:15–17:55 (CEST)
 
Room L1
Posters on site
| Attendance Thu, 18 Apr, 16:15–18:00 (CEST) | Display Thu, 18 Apr, 14:00–18:00
 
Hall X3
Posters virtual
| Attendance Thu, 18 Apr, 14:00–15:45 (CEST) | Display Thu, 18 Apr, 08:30–18:00
 
vHall X3
Orals |
Tue, 08:30
Thu, 16:15
Thu, 14:00
Planetary science is entering an exciting new technological era with advanced spacecraft providing the most in-depth view of planetary bodies in our Solar System, together with large aperture telescopes like JWST that will characterize the physics and chemistry of exoplanets in our galaxy. From the terrestrial and gas giant planets in our Solar System, to the exoplanet population of super-Earths and sub-Neptunes, rocky worlds, and gaseous planets like hot Jupiters, coupled observational and modeling efforts are needed in order to understand planetary diversity. In this session, we welcome contributions spanning observational and theoretical research that seeks to better understand the properties of planets both within and beyond the Solar System. In the coming decades, the main avenue for characterizing exoplanets will be through observations of their atmospheres. Since an in-depth study of every planet’s atmosphere is becoming increasingly impractical with the ever-growing number of known exoplanets, a comparative planetology approach, with tools including parameter surveys and statistical techniques, is increasingly important. Therefore, we invite works on the nature of planetary atmospheres, especially those with a comparative viewpoint. Of the many exoplanet systems that JWST has started to observe, the Trappist-1 system is one of the most exciting, with 7 transiting terrestrial-sized worlds. In this session, we also welcome efforts related to the formation, evolution and habitability potential of planets in this fascinating system.

Orals: Tue, 16 Apr | Room 1.31/32

Chairpersons: Daniel Williams, Neil Lewis
08:30–08:40
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EGU24-22029
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ECS
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solicited
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Highlight
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On-site presentation
Denis Sergeev
We cannot truly understand the general principles that govern planetary processes by studying only one planet or using only one modelling framework. Fortunately, continuing leaps in solar system exploration and recent exoplanetary discoveries, accelerated by the advent of JWST, allow us to start drawing connections between solar system planets and exoplanets — applying the vast knowledge of Earth and its neighbours to more distant worlds, and vice versa. To this end, solar system objects can offer analogues of some of the more exotic exoplanets, e.g. Jupiter's moon Io as an ultra-hot geologically active rocky planet analogue, or Venus as a habitable-zone Earth-like planet with a decidedly non-Earth climate. Within the solar system itself, a lot of atmospheric and geologic phenomena are present on more than one planet: dust devils are observed on both Earth and Mars, Earth's hydrological cycle has its methane counterpart on Titan, to name but a few. On the other hand, expanding our understanding of exoplanets places our own solar system within the broader context of planetary formation, architectures, atmospheres, and habitability.
 
At the same time, a smorgasbord of numerical models, including 3D general circulation models of the atmosphere, are now routinely being applied to different planets, both to test our theory, predict and interpret observations. Drawing from the success stories in the Earth climate community, it is now recognised that benchmarking and comparing the behaviour of numerical models through intercomparison projects is one of the key ways to advance our knowledge. This has a variety of benefits to the planetary science, from better planning for future observations to identifying bugs in the code to feeding back the model improvements to the Earth climate community. Recently, this effort has been re-invigorated under the CUISINES framework, an international effort to systematically contrast and compare models of various complexity for a range of different planets.
 
In this talk, I will first demonstrate how a state-of-the-art 3D climate model can be used to study different planetary atmospheres, from extrasolar hot Jupiters to temperate rocky planets. Using this model as an example, I will discuss some lessons that can be learnt in building planetary climate models. I will then give some highlights of the recent model intercomparisons for exoplanets and solar system planets. I will conclude with a discussion on how model intercomparison projects benefit both planetary and Earth-focused science.

How to cite: Sergeev, D.: Shall I compare thee to a distant world? The importance of inter-planet and inter-model comparative studies., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22029, https://doi.org/10.5194/egusphere-egu24-22029, 2024.

08:40–08:50
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EGU24-11239
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ECS
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On-site presentation
Orkun Temel, Ozgur Karatekin, Víctor Apéstigue Palacio, Toledo Daniel, Ignacio Arruego, Fulvio Franchi, German Martinez, and Cem Berk Senel

Convective instabilities in the lowermost part of the atmosphere, so called the planetary boundary layer, can lead to the formation of convective vortices and form dust devils both on Earth and Mars. We performed mesoscale simulations for a Mars-analog terrestrial site, Makgadikgadi Pan - Botswana [1,2], where a state-of-the art field campaign was conducted to investigate the terrestrial dust devils, and the InSight landing site [3] using WRF/MarsWRF models [4,5]. We then combined our atmospheric modeling with in-situ observations of wind and pressure to perform a comparative boundary-layer meteorology study. We focused on the length and time of scales of turbulence and investigated the turbulent spectrum.

[1] Toledo, D., Apéstigue, V., Arruego, I., Montoro, F., Martinez-Oter, J., Serrano, F., Yela, M., Carrasco-Blázquez, I. and Franchi, F., 2022, September. Investigating dust devils on Mars through the Makadikadi Salt Pans analogue (Botswana). In European Planetary Science Congress (pp. EPSC2022-485).
[2] Toledo, D., Apéstigue, V., Martinez-Oter, J., Franchi, F., Serrano, F., Yela, M., De La Torre Juarez, M., Rodriguez-Manfredi, J.A. and Arruego, I., 2023. Using the Perseverance MEDA-RDS to identify and track dust devils and dust-lifting gust fronts. Frontiers in Astronomy and Space Sciences, 10, p.1221726.
[3] Lorenz, R.D., Spiga, A., Lognonné, P., Plasman, M., Newman, C.E. and Charalambous, C., 2021. The whirlwinds of Elysium: A catalog and meteorological characteristics of “dust devil” vortices observed by InSight on Mars. Icarus, 355, p.114119.
[4] Temel, O., Senel, C.B., Porchetta, S., Muñoz-Esparza, D., Mischna, M.A., Van Hoolst, T., van Beeck, J. and Karatekin, Ö., 2021. Large eddy simulations of the Martian convective boundary layer: towards developing a new planetary boundary layer scheme. Atmospheric Research, 250, p.105381.
[5] Temel, O., Bricteux, L. and van Beeck, J., 2018. Coupled WRF-OpenFOAM study of wind flow over complex terrain. Journal of Wind Engineering and Industrial Aerodynamics, 174, pp.152-169.

How to cite: Temel, O., Karatekin, O., Apéstigue Palacio, V., Daniel, T., Arruego, I., Franchi, F., Martinez, G., and Senel, C. B.: Turbulence statistics of terrestrial Mars-analog and Martian dust devils, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11239, https://doi.org/10.5194/egusphere-egu24-11239, 2024.

08:50–09:00
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EGU24-4489
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On-site presentation
Ralph Lorenz

 

Convective vortices, and their particle-laden counterparts dust devils, are an important feature of the meteorology of both Mars and terrestrial desert areas. In addition to being interesting phenomena in their own right, they can cause occasional damage and even death.  

The last 12 years has seen the generation of statistically-robust catalogs of vortex encounters from long-lived (>1000 Sol) landers and rovers equipped with meteorological instrumentation, namely MSL, InSight and Mars 2020. 

 Although previous landers (Phoenix and Pathfinder, lasting ~100 Sols) yielded catalogs that were enough to indicate useful analytic function descriptions of vortex population functions (e.g. power laws or exponentials of number versus measured pressure drop), the new generation of missions provide much more robust statistics, and also have had more extensive instrumentation, permitting the documentation of wind speed, dust loading and even seismic characteristics of vortex encounters.

In the 2000s, the Mars statistics were in fact rather better than those available for the Earth, but the advent of inexpensive and low-power data logging systems with flash memory permitted the long-duration (months) acquisition of high-cadence (>1/second) pressure and other data required to detect small vortices in unattended field measurement campaigns. Inexpensive timelapse cameras have also permitted optical surveys of dust devils that are comparable with those from Mars landed and orbital missions.

In many respects the populations of vortex events are surprisingly similar on the two worlds, when expressed as a normalized peak pressure drop (pressure drop divided by ambient pressure : this quantity is proportional to the peak wind speed at the wall of the vortex).  The cumulative rate of encounters typically varies as a power law with an exponent of about -2, and Martian rates are a factor of several higher than those on Earth.  Although the convective heating rates of the respective surfaces are somewhat different, a key difference is that the Martian Planetary Boundary Layer, which sets the upper limit on vortex size, is much deeper, and Martian dust devils are typically larger than Earth’s as a result.  

I will review these population functions and their implications for meteorology, dust lifting and safety.

How to cite: Lorenz, R.: Comparing the Dust Devil Vortex Populations on Mars and Earth, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4489, https://doi.org/10.5194/egusphere-egu24-4489, 2024.

09:00–09:10
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EGU24-2151
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On-site presentation
Jeanne Davoult and Yann Alibert

The search for Earth-like planets is a subject of great importance in the world of planetology today. Detecting such planets is challenging and requires a great deal of observation time. With future missions such as PLATO or LIFE, one of the main objectives of which is to detect small, moderate-temperature planets like the Earth, it is important to understand in what types of systems these plants form and around which stars we can expect to detect them. We present here a theoretical statistical study of the most favorable conditions for a planetary system to host an ELP (Earth-like planet). Based on three populations of synthetic planetary systems generated using the Bern model around three different types of stars, this study aims to create a profile of a typical system that harbors an ELP. By using an observational bias, we generate new populations that can be compared to observed systems. We initially examine the distribution of ELPs across different categories of theoretical and observed architectures. The changes in architecture resulting from the application of a bias are also investigated, highlighting the relationship between "theoretical" and "biased" architectures. A more detailed analysis is then conducted, linking the “biased” architecture of a system with the physical properties of its innermost observable planet, in order to establish the most favorable conditions for the presence or absence of an ELP in a system. Several quantities, such as the mass, radius, period and water fraction of this planet, emerge as correlated with the presence or the absence of an ELP.

How to cite: Davoult, J. and Alibert, Y.: Earth-like planets hosting systems: architectures and properties, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2151, https://doi.org/10.5194/egusphere-egu24-2151, 2024.

09:10–09:20
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EGU24-15714
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ECS
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Virtual presentation
María Ruíz-Pérez, Jorge Pla-Garcia, Manuel de la Torre-Juarez, and Scot Rafkin

The Curiosity rover has moved more than 31 km from the landing site at the very bottom of the crater and has climbed more than ∼750 m into the Mnt. Sharp foothills over more than five Martian years. A significant change in temperatures and pressures measured by the REMS monitoring weather station aboard the Curiosity rover has been detected during that traverse.
On Earth deep valleys, like the ones in Alps, and craters on Mars like Gale accumulate masses of cold air at night, a.k.a. cold pools, at the bottom of the craters. These pockets of cold air change aspects of local micrometeorology at the bottom of a deep valley compared to the slopes. Downslope winds originating from both Mnt. Sharp and crater rims converge at the very bottom of the crater floor and may produce a vortex in the very stable and shallow nocturnal air mass [Rafkin et al. 2016]. This flow would prevent the nighttime accumulation of any tracer along the slopes above the cold pool and facilitate the convergence and accumulation of tracers in the bottom of the crater. The exception is during the northern hemisphere winter (around Ls 270 when strong northerly winds tend to scour the crater air mass day and night [Pla-García et al. in 2019].
As Curiosity ascends, we can examine whether these cold air masses exist at the very bottom of the crater and whether the rover moves away from them when reaching a specific height through Mnt. Sharp slopes. One indication is an increase in nighttime temperatures as the rover climbs Mt. Sharp’s slope. Those interannual increments of nighttime temperatures at Gale show a smooth variation within the lower layers before changing scenarios from landing location and tosol’s (Figure). To distinguish this effect from seasonal trends, an analysis of potential temperatures was performed (Figure). Comparing minimum to average temperatures in Figure allows to relate the changes to seasonal or other effects. The figure shows the annual evolution of the Martian air temperature using a Fourier adjustment. Modeling and observations strongly suggest that the rover has ascended to elevations above the cold pool at the bottom of the crater [Ruíz-Pérez et al. 2024 in preparation].

How to cite: Ruíz-Pérez, M., Pla-Garcia, J., de la Torre-Juarez, M., and Rafkin, S.: Cold pool pockets develop at the bottom of Gale crater (Mars), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15714, https://doi.org/10.5194/egusphere-egu24-15714, 2024.

09:20–09:30
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EGU24-20933
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On-site presentation
Joel Campbell, Zhaoyan Liu, Bing Lin, Jirong Yu, and Jihong Geng

We investigate the feasibility of measuring methane on Mars using a satellite based lidar at 3.3 um which has the advantage over passive instruments in being able to measure methane at night. Line selection, power requirements, signal to noise, and other details are discussed. Comparisons with other technologies are made. Previous measurements are discussed and the possible advantages of measurements that Lidar can obtain are presented. Subterranean life and other processes are investigated as a possible origin of methane on Mars. Comparisons of similar subterranean life on earth are used as a model for possible subterranean life on Mars and elsewhere.

 

How to cite: Campbell, J., Liu, Z., Lin, B., Yu, J., and Geng, J.: On the feasibility of measuring methane on Mars using 3.3 um lidar from space, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20933, https://doi.org/10.5194/egusphere-egu24-20933, 2024.

09:30–09:40
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EGU24-6826
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Virtual presentation
Thomas Fauchez, Linda Sohl, Guillaume Chaverot, Duncan Christie, Russell Deitrick, Jacob Haqq-Misra, Sonny Harman, Nicolas Iro, Kostas Tsigaridis, and Geronimo Villanueva

The exoplanet community possesses an incredible variety of models to match the astronomical diversity of exoplanets. Those models are used to either predict or interpret exoplanet data. However, contrary to Earth science, we have no existing ground truth to validate those models. Meanwhile, we would still learn a lot from benchmarking exoplanet models together to increase the robustness in our data prediction and interpretation, to identify bugs and to highlight model features that would require additional developments.

The Climates Using Interactive Suites of Intercomparisons Nested for Exoplanet Studies (CUISINES) Working Group of NASA’s Nexus for Exoplanet Systems Science (NExSS) supports a systematized approach to evaluating the performance of exoplanet models, and provides here a framework for conducting community-organized exoplanet Model Intercomparison Projects (exoMIPs). The CUISINES framework adapts Earth climate community practices specifically for the needs of the exoplanet researchers, encompassing a range of model types, planetary targets, and parameter space studies. 

In this presentation, we will give updates on the various exoMIPs and we will provide insights on our findings to make an exoplanet model intercomparison a success on short and long timescales.

How to cite: Fauchez, T., Sohl, L., Chaverot, G., Christie, D., Deitrick, R., Haqq-Misra, J., Harman, S., Iro, N., Tsigaridis, K., and Villanueva, G.: The CUISINES 2024 menu: Updates and progress on a large exoplanet model intercomparison framework, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6826, https://doi.org/10.5194/egusphere-egu24-6826, 2024.

09:40–09:50
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EGU24-17748
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On-site presentation
Benjamin Taysum, Iris van Zelst, John Lee Grenfell, Franz Schreier, Juan Cabrera, and Heike Rauer

With ongoing missions such as the James Webb Space Telescope and planned initiatives such as the Large Interferometer For Exoplanets (LIFE), the detection and attribution of biosignatures in exoplanetary atmospheres increasingly becomes a point of focus. However, in order to assess how different biosignatures manifest themselves in the atmospheres of rocky exoplanets in contrast to our temperate Earth, improved insights into the maintenance of earthlike atmospheric biosignatures in different atmospheres are necessary. 

Here, we identify and investigate the main processes and possible couplings between atmospheric climate and photochemistry for earthlike planets across the inner habitable zone. We also study the detectability of the modelled spectral features with the LIFE simulator to assess how the atmospheres of planets with an earthlike biosphere may appear to future missions like the LIFE interferometer. 

We use the global-mean, stationary, coupled climate-chemistry column model, 1D-TERRA, to simulate the climate and chemistry of planetary atmospheres at different distances from the Sun, initially assuming Earth's planetary parameters and evolution. We run six scenarios: we assume rocky exoplanets with Earth’s biomass fluxes forming around the Sun with insolation from 100% to 150% in steps of 10%. From the resulting output of temperature and composition profiles, we calculate theoretical transmission and emission spectra using a radiative transfer model (GARLIC).

The models show moderate ocean evaporation as the planet moves closer to the Sun, which results in water-vapour-rich atmospheres with the partial pressures of steam ranging from about 0.01 bar (modern Earth insolation, S=1) up to 0.6 bar (S=1.5). In the latter model,  the global mean surface temperature increases to 365.4K. This is mainly due to the higher energy input and the enhanced greenhouse effect due to increased amounts of water vapour in the atmosphere. Regarding key atmospheric biosignatures, ozone, surprisingly, mostly survives in the middle atmosphere in all scenarios, mainly because hydrogen oxide abundances, a catalytic sink for ozone, are prevented from strongly increasing due to reactions with nitrogen oxides. Methane is strongly removed for insolations above 20% those of Earth, because rising water abundances strongly increase hydroxyl (OH) (via UV photolysis) the main sink for methane. Nitrous oxide (N2O) generally survives, mainly due to trade-off effects where enhanced photolytic loss on upper layers due to higher insolation is counterbalanced by stronger absorption of photons on the lower layers due to enhanced water from evaporation. Hydrogen escape rates are 0.690 Tg/yr for the highest insolation scenario. Abiotic oxygen production associated with atmospheric escape of atomic hydrogen as well as catalytic in-situ recycling of oxygen atoms present in HOx species, lead to an increase in the O2 vmr to 0.35 mol/mol on increasing solar insolation from S = 1.0-1.3. For all scenarios, the simulated transmission and emission spectra show clearly evident H2O and CH4 features in the near to mid IR, strong CO2 absorption around 15 microns, and O3 absorption at around 9.6 microns.

How to cite: Taysum, B., van Zelst, I., Grenfell, J. L., Schreier, F., Cabrera, J., and Rauer, H.: Maintenance of atmospheric biosignatures across the inner habitable zone for earthlike planets, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17748, https://doi.org/10.5194/egusphere-egu24-17748, 2024.

09:50–10:00
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EGU24-9761
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On-site presentation
Lena Noack and Caroline Brachmann

Many factors influence the long-term evolution of the atmosphere of a rocky planet, including star-planet interactions and late accretion of volatiles. However, for planets where gravity is low enough for a primordial atmosphere to escape (i.e. roughly Earth-size and smaller), the main factor driving the atmospheric evolution will be volcanic outgassing from the interior. 

While for planets in the habitable zone, where liquid water may exist that could allow for an Earth-like carbon-silicate cycle, planets closer to their host star have been suggested to have Venus-like, thick CO2-dominated atmospheres. Our study focusses on the question, how basic planetary parameters such as size, core mass fraction, and surface regime (either stagnant-lid or mobile, such as plate tectonics) may impact the atmosphere, specifically the range of atmospheric pressures as well as their composition, for warm planets where condensation of water as well as an efficient carbon cycle can be excluded. 

We show, that planets with a stagnant lid tend to be hotter in their interior due to the isolating behaviour of the lithosphere, but at the same time tend to have much reduced outgassing efficiencies. At the same time, since volcanic outgassing at the surface of a planet is directly influenced by partial pressures in the atmosphere, compositional variations appear between stagnant-lid or mobile-lid planets, as well as between low-mass and high-mass rocky planets.

Observations with JWST looking at warmer planets (i.e. inside the inner boundary of the habitable zone) might therefore give first-order indications on the outgassing efficiency (coupled with the erosion efficiency of the atmosphere) and surface regime of these rocky planets.

How to cite: Noack, L. and Brachmann, C.: Connecting the interior to the atmosphere: should atmospheres of warm rocky planets differ for stagnant-lid and mobile surface regimes?, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9761, https://doi.org/10.5194/egusphere-egu24-9761, 2024.

10:00–10:10
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EGU24-17474
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ECS
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On-site presentation
Rob Spaargaren, Maxim Ballmer, Stephen Mojzsis, and Paul Tackley
Based on stellar compositions, we know that rocky exoplanets show a diversity in interior compositions, and therefore mantle mineralogies. The mantle mineralogy controls physical parameters of the mantle, such as viscosity, and therefore strongly affects thermal and dynamical evolution of the interior. However, it is unknown whether mantle mineralogy plays a role in establishing a planets surface dynamic regime (e.g., mobile lid, stagnant lid, episodic lid), which plays a pivotal role in determining a planets’ habitability. Here, we investigate the long-term dynamical evolution of Earth-sized planets with a range of mantle mineralogies based on stellar compositions.

We explore the long-term evolution of an Earth-sized rocky planet, varying mantle mineralogy, by employing a 2D global-scale model of thermochemical mantle convection. We include the effects of composition on planet structure, mantle physical properties, and mantle melting. We investigate how composition affects thermal evolution, and whether it has an effect on the propensity of a planet towards plate tectonics-like behaviour.

We find that density contrast between crustal material and the underlying mantle, governed by mantle Fe content, plays a vital role in determining dynamical behaviour. A very light crust is unable to subduct, locking a planet into a stagnant lid regime. Meanwhile, a very dense crust may settle at the core-mantle boundary, unable to be re-entrained into the overlying mantle. This leaves a depleted, infertile mantle and could potentially lock most of the planets water and heat producing element budget into the lowermost mantle. Mantle viscosity,  governed by Mg/Si ratio, plays a primary role in discerning between an episodically mobile and a fully stagnant lid, but has little effect on the propensity towards a fully mobile lid regime. Therefore, while composition plays a major role in determining planet material properties and dynamics, its effects on habitability are not straightforward.

 

How to cite: Spaargaren, R., Ballmer, M., Mojzsis, S., and Tackley, P.: Connecting exoplanet mantle mineralogy to surface dynamic regime, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17474, https://doi.org/10.5194/egusphere-egu24-17474, 2024.

Coffee break

Orals: Tue, 16 Apr | Room L1

Chairpersons: Emeline Bolmont, Maggie Thompson, Elsa Ducrot
16:15–16:25
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EGU24-19230
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ECS
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On-site presentation
Yutong Shan, Petra Hatalova, Hugo Tabernero, Anina Timmermann, Elena Mamonova, and Stephanie Werner

Planets are assembled from the same material as their parent stars. Therefore, stellar chemical abundance measurements provide important constraints on the formation, composition, and interior structure of exoplanets. M dwarfs are the most prolific hosts of low-mass, rocky, potentially habitable exoplanets. However, owing to the complexity of their atmospheres (which are marred by molecular absorption), elemental abundances of M dwarfs are notoriously difficult to measure. For key rock-forming elements, state-of-the-art abundance precisions attainable from high-resolution spectroscopy of M dwarfs can be up to an order of magnitude poorer than that for sun-like stars. This would mean a comprehensive characterisation of planets around M dwarfs may be more elusive. We explore examples of consequences for uncertainties in exoplanet modelling, such as condensation sequences, bulk compositions, and core-mantle fractions. We discuss what is required from the stellar science community to make progress.  

How to cite: Shan, Y., Hatalova, P., Tabernero, H., Timmermann, A., Mamonova, E., and Werner, S.: Current limitations in chemical abundance measurements for M dwarfs and implications for exoplanet characterisation  , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19230, https://doi.org/10.5194/egusphere-egu24-19230, 2024.

16:25–16:35
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EGU24-7320
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On-site presentation
Meng Tian and Kevin Heng

Hydrogen- and helium-rich primordial atmospheres of small rocky planets, formed as a result of planetary accretion, are subject to subsequent modifications of geochemical outgassing. Two outcomes are possible: a secondary atmosphere forms if the outgassing completely replaces the primordial atmosphere, or a hybrid atmosphere results if the primordial atmosphere undergoes a partial loss with its leftover reacting with the newly outgassed species. We constructed a zero-dimensional thermodynamic model where both scenarios can be consistently simulated. The model assumes chemical equilibrium and admits input parameters of oxidation and sulfidation states of the mantle, melt temperature, atmospheric nitrogen content, surface pressure (for secondary atmosphere models), and hydrogen partial pressure (for hybrid atmosphere models). It computes the chemical compositions of outgassing, namely, the volume mixing ratios of various gaseous species. Non-ideal gas behaviors are accounted for in the model and the calculated secondary and hybrid atmospheres both exhibit a vast chemical diversity. For example, hydrogen-rich atmospheres, conventionally deemed of primordial origin, can also stem from interior outgassing. By Monte Carlo sampling in the possible ranges of the input parameters, we found that outgassed methane-dominated atmospheres, regardless of secondary or hybrid, require rather specific conditions: (1) a reduced rocky mantle; (2) relatively low melt temperatures in comparison to those of basaltic or peridotitic melts; (3) relatively high atmosphere pressures (> c.a. 10 bar) on the rocky surface. Moreover, we found that the abundance ratio of CO2 and CO can serve as a powerful diagnostic of oxygen fugacity of rocky mantles, which could potentially be constrained by future James Webb Space Telescope spectra. The current model does not consider atmospheric escape, chemical kinetics or photochemistry, which awaits to be incorporated in future works.

How to cite: Tian, M. and Heng, K.: Thermodynamic modelling of the outgassing chemistry of Super Earths and sub-Neptunes: applications to secondary and hybrid atmospheres, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7320, https://doi.org/10.5194/egusphere-egu24-7320, 2024.

16:35–16:45
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EGU24-5832
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On-site presentation
Gregor J. Golabek, Tim Lichtenberg, Lotte M. Bartels, Paul J. Tackley, Tobias Meier, and Dan Bower

The dawn of high-resolution observations with the James Webb Space Telescope will enable spatially resolved observations of ultrashort-period rocky exoplanets. Some of these planets orbit so closely to their star that they lack an atmosphere [1], which gives direct access to their surfaces and opens a window to infer their geodynamics [2]. The physical parameters of the ultrashort-period sub-Earth GJ 367 b have been observationally constrained to a planetary radius of about 0.72 to 0.75 Earth-radii and a mass between 0.48 and 0.55 Earth-masses, implying a density of 6200 to 8500 kg/m3 [3, 4], which puts this planet in a Mercury-like interior regime with a thin mantle overlying a fractionally large core.

The dayside temperature ranges between 1500 to 1800 K, thus suggesting the presence of a permanent magma ocean or dayside magma pond on the surface, induced by stellar irradiation. The large uncertainty on the age of the stellar system, between 30 Myr [4] and about 8 Gyr [3], however, introduce severe uncertainties related to the compositional and thermal evolution of the planetary mantle. In this study we perform global 2D spherical annulus StagYY simulations [5, 6] of solid-state mantle convection and surface melting with the goal to constrain the geometric and compositional properties of the planet. Constraining the spatial dimensions of thermodynamic properties of partially molten, atmosphere-less planets like GJ 367 b offers unique opportunities to constrain the compositional fractionation during magma ocean epochs and provides avenues to constrain the delivery and loss cycle of atmophile elements on strongly irradiated exoplanets.

References:

[1] L. Kreidberg and 18 co-authors. Absence of a thick atmosphere on the terrestrial exoplanet LHS 3844b. Nature, 573:87–90, 2019.

[2] T. G. Meier, D. J. Bower, T. Lichtenberg, P. J. Tackley, and B.-O. Demory. Hemispheric Tectonics on LHS 3844b. Astrophys. J. Lett., 908:L48, 2021.

[3] K.W.F. Lam and 78 co-authors. GJ 367 b: A dense, ultrashort-period sub-earth planet transiting a nearby red dwarf star. Science, 374:1271–1275, 2021.

[4] W. Brandner, P. Calissendorff, N. Frankel, and F. Cantalloube. High-contrast, high-angular resolution view of the GJ367 exoplanet system. Mon. Notices Royal Astron. Soc., 513:661–669, 2022.

[5] J. W. Hernlund and P. J. Tackley. Modeling mantle convection in the spherical annulus. Phys. Earth Planet. Int., 171:48–54, 2008.

[6] P. J. Tackley. Modelling compressible mantle convection with large viscosity contrasts in a three-dimensional spherical shell using the yin-yang grid. Phys. Earth Planet. Int., 171:7–18, 2008.

How to cite: Golabek, G. J., Lichtenberg, T., Bartels, L. M., Tackley, P. J., Meier, T., and Bower, D.: Magma oceanography of the dense, ultrashort-period sub-Earth GJ 367 b, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5832, https://doi.org/10.5194/egusphere-egu24-5832, 2024.

16:45–16:55
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EGU24-18489
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ECS
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Highlight
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On-site presentation
Sebastian Zieba, Laura Kreidberg, Elsa Ducrot, Michaël Gillon, Caroline Morley, Laura Schaefer, Patrick Tamburo, Daniel D. B. Koll, Xintong Lyu, Lorena Acuña, Eric Agol, Aishwarya R. Iyer, Renyu Hu, Andrew P. Lincowski, Victoria S. Meadows, Franck Selsis, Emeline Bolmont, Avi M. Mandell, and Gabrielle Suissa

Seven rocky planets orbit the nearby dwarf star TRAPPIST-1, providing a unique opportunity to search for atmospheres on small planets outside the Solar System. Thanks to the recent launch of the James Webb Space Telescope (JWST), possible atmospheric constituents such as carbon dioxide (CO2) are now detectable. Recent JWST observations of the innermost planet TRAPPIST-1 b showed that it is most probably a bare rock without any CO2 in its atmosphere. Here we report the detection of thermal emission from the dayside of TRAPPIST-1 c with the Mid-Infrared Instrument (MIRI) on JWST at 15 µm. We measure a planet-to-star flux ratio of 421 +/- 94 parts per million (ppm), which corresponds to an inferred dayside brightness temperature of 380 +/- 31 K. This high dayside temperature disfavours a thick, CO2-rich atmosphere on the planet. The data rule out cloud-free O2/CO2 mixtures with surface pressures ranging from 10 bar (with 10 ppm CO2) to 0.1 bar (pure CO2). A Venus-analogue atmosphere with sulfuric acid clouds is also disfavoured at 2.6 sigma confidence. Thinner atmospheres or bare-rock surfaces are consistent with our measured planet-to-star flux ratio.

How to cite: Zieba, S., Kreidberg, L., Ducrot, E., Gillon, M., Morley, C., Schaefer, L., Tamburo, P., Koll, D. D. B., Lyu, X., Acuña, L., Agol, E., Iyer, A. R., Hu, R., Lincowski, A. P., Meadows, V. S., Selsis, F., Bolmont, E., Mandell, A. M., and Suissa, G.: No thick carbon dioxide atmosphere on the rocky exoplanet TRAPPIST-1 c, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18489, https://doi.org/10.5194/egusphere-egu24-18489, 2024.

16:55–17:05
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EGU24-20183
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ECS
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Highlight
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On-site presentation
Elsa Ducrot, Pierre-Olivier Lagage, and Michiel Min and the ExoMIRI Team

The first JWST/MIRI photometric observations of TRAPPIST-1 b allowed for the detection of the thermal emission of the planet at 15 microns, suggesting that the planet could be a bare rock with a zero albedo and no redistribution of heat. Here we present five new occultations of TRAPPIST-1 b observed with MIRI in an additional photometric band at 12.8 microns.  In this presentation we present the results from a joint fit of the 10 eclipses and derive a planet-to-star flux ratio of 452 +/- 86 ppm and 775 +/-90 ppm at 12.8 microns and 15 microns, respectively. 
We show how we tested a large range of models and found that the data can be well fitted by either an airless planet model with an unweathered (fresh) ultramafic surface, that could be indicative of relatively recent geological processes, or, more surprisingly, by a thick pure CO2 atmosphere with photochemical hazes that create a temperature inversion and results in the CO2 feature being seen in emission. 
Our results highlight the challenges in accurately determining a planet's atmospheric or surface nature solely from broadband filter measurements of its emission, but also point towards two very interesting scenarios that will be further investigated with the forthcoming phase curve of TRAPPIST-1 b+c.

How to cite: Ducrot, E., Lagage, P.-O., and Min, M. and the ExoMIRI Team: Combined analysis of the 12.8 and 15 microns JWST/MIRI eclipse observations of TRAPPIST-1 b, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20183, https://doi.org/10.5194/egusphere-egu24-20183, 2024.

17:05–17:15
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EGU24-9116
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Highlight
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Virtual presentation
Michael Gillon and the JWST Program 3077 team

Small rocky planets are now known to be very frequent in temperate orbits around low-mass M-dwarfs. The most pressing question regarding these ubiquitous planets concerns their capacity to maintain significant secondary atmospheres despite the adverse environment (high XUV fluxes, winds) and history (long pre-main-sequence) brought by their small host stars. Here, we present the photometric observation by JWST/MIRI of the combined thermal phase curve of the two inner planets of the TRAPPIST-1 system (Cycle 2 program 3077). These observations aimed to determine if the two planets are bare rocks or not by complementing the Cycle 1 measurements of their daysides' thermal emission at 15 microns (for b and c) and 12.8 microns (for b).

How to cite: Gillon, M. and the JWST Program 3077 team: The double phase curve of TRAPPIST-1b and c at 15 microns, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9116, https://doi.org/10.5194/egusphere-egu24-9116, 2024.

17:15–17:25
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EGU24-1746
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ECS
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On-site presentation
Gwenaël Van Looveren, Manuel Güdel, Sudeshna Boro Saikia, and Kristina Kislyakova

JWST is currently at the forefront in the search for exoplanet atmospheres. However, the observation of atmospheres of Earth-like planets pushes the limits of the instruments, often requiring multiple observations to be combined. Their interpretation requires complementary theoretical studies to test plausible atmospheric models. We aim to determine the atmospheric survivability of rocky planets around late M-type dwarfs by modelling the upper atmosphere of the TRAPPIST-1 planets' response to incoming stellar extreme ultraviolet and X-ray (XUV) radiation. This is done using a self-consistent thermo-chemical code to create a grid of models simulating possible atmospheres. Specifically we study the atmospheric mass loss due to Jeans escape induced by XUV radiation. Our models indicate that even Jeans escape is catastrophically large for these N2 or CO2 dominated atmospheres over evolutionary timescales, which has important observational implications.

How to cite: Van Looveren, G., Güdel, M., Boro Saikia, S., and Kislyakova, K.: Airy worlds or barren rocks? On the survivability of secondary atmospheres around the TRAPPIST-1 planets., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1746, https://doi.org/10.5194/egusphere-egu24-1746, 2024.

17:25–17:35
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EGU24-17280
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ECS
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On-site presentation
Alexandre Revol, Emeline Bolmont, Mariana V. Sastre, Anne-Sophie Libert, Gabriel Tobie, and Sergi Blanco-Cuaresma

Recent JWST observations of rocky planets, such as TRAPPIST-1, and the increasing number of rocky planets discovered orbiting close to their host star, strongly motivates the improvement of tidal modeling.
Beside, recent JWST observations of the thermal emission from TRAPPIST-1 b and c have provided constraints on their atmospheres (Greene et al. 2023; Ih et al. 2023; Zieba et al. 2023; Lincowski et al. 2023). 
In this context, It is crucial to use a coherent tidal model that encapsulates the complex response of rocky planets to stress, to understand the evolution of exoplanets and interpret new data.

Our presentation will focus on recent developments on the implementation of the formalism of Kaula (1964) in the N-body code Posidonius (Blanco-Cuaresma & Bolmont 2017; Bolmont et al. 2020).
This formalism consists in using a decomposition of the tidal potential into Fourier harmonic modes, which allows to account for the frequency dependence of the tidal response of rocky bodies.
It makes it general enough to take into account for any type of internal structure, as well as the presence of ice or surface liquid water.
We will present our results on the rotational state of TRAPPIST-1 planets, revisiting the assumption of the perfect synchronization state resulting from tidal evolution. 
Given that the rotational state influences the heat redistribution regime, precise estimation of their rotational state is critical.
Various internal structures were explored with the Burnman code (Cottaar et al. 2014; Myhill et al. 2021)., considering compositions and core sizes compatible with mass and radius estimations from Agol et al. (2021).

Our simulations showed that planet-planet interactions induce rapid variations in the mean motions of the planets. 
These variations occur too quickly for tides to maintain synchronized rotation states with the mean motion. 
This results in sub-stellar point drifts, causing planets to complete full solar days with periods ranging from 42 to 103 years depending on the planet. 
The competition between mean motion variations and tidal damping, and thus sub-stellar drifts, is contingent on the internal structure of the planet under consideration. 
As a result, remnant rotation is expected to facilitate the redistribution of heat on the planet's surface, modifying habitability conditions by mitigating the cold-trap effect on the night side (Turbet et al. 2016) and redistributing cloud formation on the day side (Turbet et al. 2021).
Additionally, we will present preliminary results on the coupling between the spin and the orbital evolution of planets in compact mean motion resonances (MMRs), in particular with the presence of obliquity spin-orbit resonances (SOR), on time transit variations (TTV) and on the mean motion resonances for the TRAPPIST-1 system and the potential observability of such effects.

How to cite: Revol, A., Bolmont, E., Sastre, M. V., Libert, A.-S., Tobie, G., and Blanco-Cuaresma, S.: Improving tidal interaction for compact N-body planetary system., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17280, https://doi.org/10.5194/egusphere-egu24-17280, 2024.

17:35–17:45
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EGU24-18447
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ECS
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On-site presentation
Siddharth Bhatnagar, Emeline Bolmont, Maura Brunetti, Jérôme Kasparian, Martin Turbet, Ehouarn Millour, Francis Codron, and Alexandre Revol

Ocean modelling is often sidelined by exoclimate modellers, mostly due to the associated computational expense of spinning up dynamic oceans. However, oceanic heat transport can critically impact the climate and observables for M-planets in the middle of their habitable zones (e.g., [1]) like TRAPPIST-1e. The oceanic description can also affect the number of final stable climatic states of the planet ([2]). Short of using a fully dynamic ocean model, a compromise used in most exoplanet General Circulation Models (GCMs) is a slab ocean model without oceanic heat transport.

Here, we will first present our improved compromise - the new dynamical slab ocean model integrated into the Generic-PCM ([3]), previously known as the LMD Generic GCM (e.g., [4]). Our parallelisable ocean model not only accounts for sea-ice/snow evolution, but also features wind-driven ocean transport (Ekman transport), horizontal eddy diffusion and convective adjustment between oceanic layers. When coupled with the atmosphere, it effectively reproduces critical attributes observed on modern Earth, including the major oceanic heat flows, an annually averaged surface temperature of 13 C, planetary albedo of 0.32 and sea ice coverage spanning 18 million sq. km.

Further, we will delve into the implications of a dynamical slab ocean model for TRAPPIST-1e. Despite recent JWST observations indicating the lack of a (thick) atmosphere for TRAPPIST-1b ([5]) and 1c ([6]), the planets farther away from the star, like 1e, may have retained moderately thick atmospheres. Assuming this, and if 1e formed with a substantial water reservoir ([7]), it could have sustained liquid water oceans ([8]). In general, the presence of oceanic heat transport can give rise to distinct oceanic patterns, as illustrated by the “lobster” pattern observed for Proxima Centauri b by [9], in contrast to the “eyeball” pattern in [4], observed in its absence. Moreover, studies suggest that the climates of Proxima Centauri b and TRAPPIST-1e may share similarities ([4], [8]). In this context, we will present findings from our new dynamical slab ocean within the Generic-PCM for TRAPPIST-1e. These results will then be systematically compared with those of [9], which used ROCKE-3D ([10]) with a dynamic ocean model. We believe that this will help in strengthening our understanding of the climate of TRAPPIST-1e and also offer insights into comparative exoplanetary climate research. Finally, we will discuss our findings in the context of habitability, particularly emphasising the role of a dynamical ocean model in informing our understanding of habitable conditions.

 

References:

[1] Yang et al. (2019b)

[2] Brunetti et al. (2019)

[3] Forget et al. (in prep)

[4] Turbet et al. (2016)

[5] Greene et al. (2023)

[6] Zieba et al. (2023)

[7] Tian & Ida (2015)

[8] Turbet et al. (2018)

[9] Del-Genio et al. (2019)

[10] Way et al. (2017)

How to cite: Bhatnagar, S., Bolmont, E., Brunetti, M., Kasparian, J., Turbet, M., Millour, E., Codron, F., and Revol, A.: Diving into the new dynamical slab ocean of the Generic-PCM: Implications for the climate of TRAPPIST-1e, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18447, https://doi.org/10.5194/egusphere-egu24-18447, 2024.

17:45–17:55
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EGU24-801
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ECS
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On-site presentation
Diogo Quirino, Gabriella Gilli, Martin Turbet, Thomas Fauchez, Thomas Navarro, and Pedro Machado

Recent measurements of the dayside thermal emission of exoplanets TRAPPIST-1b [1] and TRAPPIST-1c [2] were made by the James Webb Space Telescope (JWST) Mid-Infrared Instrument (MIRI) F1500W filter which covers the 15-µm carbon dioxide (CO2) absorption. These photometric secondary-eclipse observations determined the dayside brightness temperature and constrained the magnitude of heat redistribution. For TRAPPIST-1c, which has a Venus-like stellar irradiation, the estimated eclipse depth is 421±94 ppm, corresponding to a dayside brightness temperature of 380±31 K, superior to Venus's equilibrium temperature. Two scenarios stem from the inferred brightness temperature: a moderate heat redistribution or an airless, non-zero bond albedo surface. The observations rendered thick, CO2-enriched atmospheres unlikely for TRAPPIST-1c, excluding a cloudy (sulphuric acid aerosols) and a clear-sky Venus-like atmosphere at a confidence of 2.6σ and 3.0σ, respectively [2].

New JWST observations (Cycle 2 GO Programme 3077) [3] will obtain thermal emission phase curve measurements for most of TRAPPIST-1c’s orbit (P = 58-hours), identifying the day-night temperature contrast. These will be sensitive to test the case of a moderate heat redistribution [4-8], eventually distinguishing it from spectral features from a rocky surface or those from an airless planet [9]. This research is crucial given that CO2–dominated atmospheres were predicted as a likely outcome of atmospheric evolution on rocky planets orbiting cooler and less massive stars (M-dwarf stars) than our Sun [10]. Owing to the CO2 high molecular weight and efficient cooling in the infrared, CO2-rich atmospheres have extremely cold thermospheres and less expanded upper atmospheres; both can improve resilience to atmospheric escape processes, offering partial protection against M-dwarf lifelong stellar activity [10]. Investigating the status of a possible atmosphere on TRAPPIST-1c is critical to understanding atmospheric evolution on M-dwarf planets.

Here, we use a 3D global circulation model of the atmosphere, the Generic-PCM [8,11-13], to simulate a modern Venus-like atmosphere on TRAPPIST-1c: CO2-dominated, 92-bar surface pressure with radiatively-active global cover of sulphuric acid aerosols [13]. We also assumed a tidally-locked planet with zero obliquity and eccentricity. We use these simulations to generate high spectral resolution thermal phase curves for three JWST/MIRI filters: F1280W, F1500W and F1800W. We analyse the relationship between phase curve parameters (hot spot offset and amplitude), temperature and large-scale circulation. We find large eastward offsets and small amplitudes compatible with an efficient day-night heat redistribution driven by a superrotating equatorial jet. In addition, we predict a smaller hot spot offset for F1500W due to upper atmosphere CO2 absorption. These results highlight the possibility of studying at least two different atmospheric levels. The absence of a large hot spot offset on TRAPPIST-1c would rule out a dense, CO2-rich, absorbing atmosphere on the planet. These results can be expanded to the ever-growing population of rocky exoplanets with Venus-like stellar irradiations to be studied in the following decades [14].

References: [1]Greene+2023.Nature.618; [2]Zieba+2023.Nature.620; [3]Gillon+2023.JWST Proposal 3077; [4]Selsis+2011.A&A.532; [5]Demory+2016.Nature.532; [6]Koll+2016.ApJ.825; [7]Kreidberg+2019.Nature.573; [8]Turbet+2016.A&A.596.A112; [9]Whittaker+2022.AJ.164; [10]Turbet+2020.Space Sci. Rev.216; [11]Forget & Leconte, 2014.Phil.Trans R.Soc.A372; [12]Wordsworth+2011.ApJL.733.L48; [13]Quirino+2023.MNRASL.523.L86; [14]Ostberg+2023.AJ.165.

Funding: This work was supported by Fundação para a Ciência e a Tecnologia (FCT) through the research grant 2023.05220.BD.

How to cite: Quirino, D., Gilli, G., Turbet, M., Fauchez, T., Navarro, T., and Machado, P.: No Venus-like atmosphere on TRAPPIST-1 c: confirmation from 3D climate modelling, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-801, https://doi.org/10.5194/egusphere-egu24-801, 2024.

Posters on site: Thu, 18 Apr, 16:15–18:00 | Hall X3

Display time: Thu, 18 Apr, 14:00–Thu, 18 Apr, 18:00
Chairpersons: Maggie Thompson, Aurélien Falco
X3.100
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EGU24-17602
Paolo Sossi, Maggie Thompson, Meng Tian, Kaustubh Hakim, and Dan Bower

Given the host of existing and upcoming observations of rocky (exo)planet atmospheres, a quantitative understanding of the key factors that control the nature and composition of atmospheres around these diverse worlds is needed. The speciation of major atmosphere-forming components around molten rocky planets, both within and beyond the solar system, is dictated by their abundances, the equilibrium chemistry between gas species, and their solubilities in the rocky interior. Moreover, as pressure increases at the atmosphere-interior interface, the thermodynamic behaviour of the gas phase diverges from that of the ideal case. Here, we combine these considerations into a new Python package, atmodeller, which is a flexible tool kit for computing the equilibrium conditions at the melt-atmosphere interface. Given a set of planetary parameters (e.g., surface temperature, planetary mass, radius, mantle melt fraction) and an initial volatile budget, atmodeller uses experimentally calibrated solubility laws, together with free energy data for gas species, to determine how volatiles partition between the atmosphere and interior of the planet. This package can be applied widely to rocky planets, from super-Earths to sub-Neptunes with gaseous envelopes. Within the H-C-N-O-S-Cl system, we investigate the diverse range of atmospheric compositions and the impact of volatile dissolution into the interior for a set of known rocky exoplanets (e.g., the TRAPPIST-1 system) based on the current observational constraints from JWST. In addition, we use atmodeller to simulate the effects of volatile solubilities and non-ideal conditions on H2-dominated super-Earth- and sub-Neptune atmospheres (in the H-O-Si system), such as that of the recently observed exoplanet K2-18 b. Atmodeller is a new tool to study rocky (exo)planets, uniquely incorporating equilibrium chemistry, volatile solubilities and gas non-ideality to establish the connection between rocky planet interiors and their atmospheres.

How to cite: Sossi, P., Thompson, M., Tian, M., Hakim, K., and Bower, D.: Diversity of rocky planet atmospheres in the H-C-O-N-S-Cl system with interior dissolution, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17602, https://doi.org/10.5194/egusphere-egu24-17602, 2024.

X3.101
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EGU24-9833
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ECS
Denis Sergeev, Ian Boutle, Hugo Lambert, Nathan Mayne, and Thomas Bendall

Convective processes are crucial in shaping exoplanetary atmospheres but are computationally expensive to simulate directly. A novel technique of simulating moist convection, especially on tidally locked exoplanets such as those orbiting TRAPPIST-1, is to use a 3D general circulation model (GCM) with a global stretched mesh. This allows us to locally refine the model resolution to a km-scale and resolve deep convection without relying on parameterization. We explore the impact of explicit vs parameterized convection on the climate of TRAPPIST-1e, a confirmed rocky exoplanet in the habitable zone and a primary candidate for atmospheric characterization. We show allowing for explicit convection in a stretched-mesh simulation results primarily in changes in cloud distribution and precipitation on a planetary scale. Nevertheless, the overall climate state is close to that produced with parameterized convection and a non-stretched mesh. Additionally, these novel simulations shed more light on the bistability of the atmospheric circulation on TRAPPIST-1e. Our methodology opens an exciting and computationally feasible avenue for improving our understanding of fine-scale 3D mixing in exoplanetary atmospheres.

How to cite: Sergeev, D., Boutle, I., Lambert, H., Mayne, N., and Bendall, T.: The impact of convection on the climate of TRAPPIST-1e in global stretched-mesh simulations, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9833, https://doi.org/10.5194/egusphere-egu24-9833, 2024.

X3.102
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EGU24-9521
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ECS
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Petra Hatalova, Ramon Brasser, Elena Mamonova, and Stephanie Werner

How multiple close-in super-Earths form around stars with masses lower than that of the Sun is still an open issue. Several recent modeling studies have focused on planet formation around M-dwarf stars, but so far no studies have focused specifically on K dwarfs, which are of particular interest in the search for extraterrestrial life. We aimed to reproduce the currently known population of close-in super-Earths observed around K-dwarf stars and their system characteristics. Additionally, we investigated whether the planetary systems that we formed allow us to decide which initial conditions are the most favorable. We performed 48 high-resolution N-body simulations of planet formation via planetesimal accretion using the existing GENGA software running on GPUs. In the simulations we varied the initial protoplanetary disk mass and the solid and gas surface density profiles. Each simulation began with 12000 bodies with radii of between 200 and 2000 km around two different stars, with masses of 0.6 and 0.8 MSun. Most simulations ran for 20 Myr, with several simulations extended to 40 or 100 Myr. The mass distributions for the planets with masses between 2 and 12 MEarth show a strong preference for planets with masses Mp < 6 MEarth and a lesser preference for planets with larger masses, whereas the mass distribution for the observed sample increases almost linearly. However, we managed to reproduce the main characteristics and architectures of the known planetary systems and produce mostly long-term angular-momentum-deficit-stable, nonresonant systems, but we required an initial disk mass of 15 MEarth or higher and a gas surface density value at 1 AU of 1500 g cm-2 or higher. Our simulations also produced many low-mass planets with Mp < 2 MEarth, which are not yet found in the observed population, probably due to the observational biases. Earth-mass planets form quickly (usually within a few million years), mostly before the gas disk dispersal. The final systems contain only a small number of planets with masses Mp > 10 MEarth, which could possibly accrete substantial amounts of gas, and these formed after the gas had mostly dissipated.

How to cite: Hatalova, P., Brasser, R., Mamonova, E., and Werner, S.: Forming rocky exoplanets around K-dwarf stars, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9521, https://doi.org/10.5194/egusphere-egu24-9521, 2024.

X3.103
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EGU24-2531
Michael Way

Trappist-1d remains an underexplored planets in the fascinating multi-planet Trappist-1 system.
Some earlier studies have indicated that it may be more of an exo-Venus than an exo-Earth [1,2].
Of course atmospheric composition and density plays a key role and this parameter space
has barely been explored. As well, since these earlier studies the insolation of 1d appears
to be almost 1% lower than earlier estimates [3,4]. A subsequent 1D study using the
lower insolation [5] finds one atmospheric composition places it in the habitable zone,
while the other in the Venus-Zone [6].  We use the ROCKE-3D General Circulation Model [7]
to examine Trappist-1d's possible climate.

[1] Wolf, E.T. (2017) ApJ 839:L1
[2] Turbet et al. (2018) A&A 612, A86
[3] Gillon et al. (2017) Nature 542, 456
[4] Agol et al. (2021) PSJ 2:1
[5] Meadows et al. (2023) PSJ 4:10
[6] Kane, S.R. et al. (2021) AJ 161:53
[7] Way, M.J. et al. (2017) ApJS 213:12

How to cite: Way, M.: Exploring Trappist-1d with a 3D GCM, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2531, https://doi.org/10.5194/egusphere-egu24-2531, 2024.

X3.104
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EGU24-11513
Ludmila Carone, Patrick Barth, Rory Barnes, Christiane Helling, Katy Chubb, and Bertram Bitsch

 

VPLANET MagmOc is a versatile magma ocean model with erosion of water vapour in the open source VPLANET framework. We
present here a major improvement of this model that includes now a) thermal emission calculated with a full radiative transfer code and b) simultaneous outgasing of H2O and CO2 with full feedback on outgassing informed by planet formation models.


We derived evolution tracks of an outgassed mixed H2O/CO2 atmosphere on TRAPPIST-1e, f and g. We find that all planets, in particular TRAPPIST-1 g, run the risk to evolve into Exo-Venuses with thick CO2 atmospheres after the magma ocean stage for an intial water budget of more than 10 terrestrial ocean (TO) of water within tens of million years.

At the inner edge of the habitable zone, on TRAPPIST-1 e, we find that the combination of H2O atmosphere loss and CO2 outgassing reduces the thermal emission on the planet such that the magma ocean stage can be almost doubled from tens of million years to 80 million years for 10 TO intial water.
We thus conclude that careful consideration has to be given to the various geophysical feedback effects as these can have a profound impact on the magma ocean evolution stage and thus on the overall water budget and the secondary atmosphere.

How to cite: Carone, L., Barth, P., Barnes, R., Helling, C., Chubb, K., and Bitsch, B.: Impact of CO2 on water outgassing on rocky planets around TRAPPIST-1 – VPLANET/MagmOcV2.0, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11513, https://doi.org/10.5194/egusphere-egu24-11513, 2024.

X3.105
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EGU24-7609
Panayotis Lavvas, Athena Coustenis, Therese Encrenaz, Benjamin Charnay, Bruno Bézard, Pierre Drossart, Amélie Gressier, Emilie Panek, Billy Edwards, Marc Ollivier, Karan Molaverdikhani, Olivia Venot, Deborah Bardet, Pierre-Olivier Lagage, and Giovanna Tinetti

Following the extensive exploration of hot and warm exoplanets over the past two decades, recent improvements in instrumental techniques, from ground and space, have allowed the detection of “temperate” exoplanets, with equilibrium temperatures ranging between 300 and 500 K. Opening this new research field will not only enlarge our comprehension of the various physical properties of exoplanets, but also reduce the comprehension gap between these objects and the planets of our solar system, and provide a key step towards the study of habitable exoplanets. Over the past few years, we have started a program [1, 2] for identifying temperate exoplanets, which would be observable with the Ariel mission in the spectroscopic mode (Tier 2 mode). Using the TESS database and analyzing the observability of the candidates with Ariel, we have selected a list of 15 targets (a gas giant, a few big Neptunes and several super-Earths/sub-Neptunes) for which spectroscopic observations with Ariel would allow a characterization of their atmosphere and possibly an identification of the main atmospheric absorbers [3]. Among this list, the sub-Neptune TOI-1759 b appears as a favorable candidate. With a radius of about 3 earth radii and a mass of about 10 earth masses, TOI-1759 b is most likely a hydrogen-rich planet orbiting a M0.0 star located at 40 pc with a revolution period of 19 days. We have calculated the thermal structure, dis-equilibrium composition and size distribution of cloud and haze particles in its atmosphere using a model that couples self-consistently the involved physical and chemical processes [4]. Cloud nucleation rates reach significant values near a pressure level of 0.35 bar, where the condensing gas species (KCl, NaCl and Zn) approach their saturation limit. We have calculated the infrared synthetic spectrum of TOI-1759 b from the visible up to 20 μm for different metallicities and different haze and cloud conditions. Feasibility studies [5] suggest that information could be retrieved about the target’s atmosphere with 16 primary transit observations with Ariel (which could be achieved over a time range of less than a year), or a single primary transit observation with the JWST.

 

[1] Encrenaz, T.  et al., Exp. Astr. 46, 31 (2018) 

[2] Encrenaz, T. et al.,  Exp. Astr. 53, 375 (2022).

[3] Encrenaz, T. et al. Poster presented at the EGU General Assembly, Vienna, April 2023.

[4] Arfaux & Lavvas, MNRAS, 515, 4753 (2022).

[5] Tinetti et al., Exp.Astr. 46, 135 (2018).

How to cite: Lavvas, P., Coustenis, A., Encrenaz, T., Charnay, B., Bézard, B., Drossart, P., Gressier, A., Panek, E., Edwards, B., Ollivier, M., Molaverdikhani, K., Venot, O., Bardet, D., Lagage, P.-O., and Tinetti, G.: A favorable sub-Neptune target for JWST and Ariel observations: TOI 1759 b, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7609, https://doi.org/10.5194/egusphere-egu24-7609, 2024.

X3.106
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EGU24-10178
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ECS
Stellar wind impact on early atmospheres around unmagnetized Earth-like planets
(withdrawn)
Ada Canet and Ana Inés Gómez de Castro
X3.107
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EGU24-11800
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ECS
First comparative exoplanetology between planets within the same system, and between young and mature sub-Neptunes
(withdrawn)
Saugata Barat and Jean-Michel Desert
X3.108
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EGU24-13378
Maria Di Paolo, David Stevens, Manoj Joshi, and Rob Hall

Due to their abundance and their observational advantages, M dwarfs offer the best chance of finding habitable planets through sheer numbers. Therefore, in the race to detect signs of life beyond the Solar System, rocky M-dwarf planets offer exciting prospects.
While the habitable zone serves as a preliminary indicator of the potential habitability of a planet, planetary climate studies are necessary in order to better assess a planet’s ability to host life. Climate is affected by numerous factors that are not considered in the classic habitable zone formulation, but can be included in climate models of varying complexity.
Oceans have a dominant impact on planetary climate, so understanding their effects is a necessary part of modelling terrestrial exoplanets in order to understand future observations.

We have conducted studies with an intermediate complexity coupled atmosphere-ocean general circulation model (FORTE2.0). Using a coupled dynamic ocean enables us to include effects of ocean circulation. Strong tidal interactions are tightly linked to the ocean vertical diffusivity and thus ocean temperature structure (including surface temperature). Taking into account the impact of ocean tides can therefore lead to significant effects on planetary climate.
We investigated the case of non synchronous terrestrial planets in close orbits in the habitable zone of their M host star. In this scenario, we have parameterised the effect of propagating tides, and analysed their impact on ocean circulation and minimum and maximum values of surface temperature. We found that ocean tides are particularly important in setting latitudinal gradients in temperature, with subsequent effects on climate and habitability.
By considering scenarios in which the magnitude of tidal forcings varies over a range of values, we were able to determine that key surface quantities (such as winds, heat flux and water flux) are subjected to change.
The repercussions that ocean vertical diffusion can have on surface quantities is noteworthy from the observational point of view, as observable features - such as cloud patterns – are shaped differently in each scenario.

How to cite: Di Paolo, M., Stevens, D., Joshi, M., and Hall, R.: Effect of ocean tidal mixing on exoplanet climates and habitability, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13378, https://doi.org/10.5194/egusphere-egu24-13378, 2024.

X3.109
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EGU24-15544
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Highlight
Tim Lichtenberg, Sascha Quanz, Lena Noack, Daniel Angerhausen, Sarah Rugheimer, Adrian Glauser, Jens Kammerer, Andrea Fortier, Michael Ireland, Denis Defrère, Hendrik Linz, Nicolas Iro, and Life Collaboration

The atmospheric characterization of a significant number of terrestrial exoplanets is a major goal of 21st century astrophysics. However, none of the currently adopted missions worldwide has the technical capabilities to achieve this goal. Here we present the LIFE mission concept, which addresses this issue by investigating the scientific potential and technological challenges of an ambitious mission employing a formation-flying nulling interferometer in space working at mid-infrared wavelengths. LIFE, in synergy with other planned future missions, will for the first time in human history enable us to understanding global biosignatures and planetary habitability in the context of the diversity of planetary systems. Breakthroughs in our understanding of the exoplanet population and relevant technologies justify the need, but also the feasibility, for future atmosphere characterization and life detection missions to investigate one of the most fundamental questions of humankind: how frequent and diverse are global biospheres in the galaxy?

How to cite: Lichtenberg, T., Quanz, S., Noack, L., Angerhausen, D., Rugheimer, S., Glauser, A., Kammerer, J., Fortier, A., Ireland, M., Defrère, D., Linz, H., Iro, N., and Collaboration, L.: Large Interferometer for Exoplanets (LIFE): characterizing the mid-infrared thermal emission of terrestrial exoplanets, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15544, https://doi.org/10.5194/egusphere-egu24-15544, 2024.

X3.110
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EGU24-16843
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ECS
A re-analysis of equilibrium chemistry in five exoplanets' atmosphere
(withdrawn after no-show)
Emilie Panek, Jean-Philippe Beaulieu, Pierre Drossart, Olivia Venot, Quentin Changeat, Ahmed F. Al-refaie, and Amélie Gressier
X3.111
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EGU24-16760
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ECS
Michaela Walterová and Marie Běhounková

Tidal effects probe the interior of celestial bodies and are an important source of information on their thermal state and the prevailing deformation mechanisms. In the case of exoplanets, estimation of quantities related to tides might add important constraints on the interior structure of those worlds that would complement the existing measurements of masses and radii [e.g., 1]. In recent years, the fluid Love number hf, which characterises the deformed figure of a rotating celestial body, has been measured for the gaseous exoplanet WASP-103b [2], and the rate of tidal dissipation has also been estimated for several extrasolar gas giants [e.g., 3]. Although not directly detectable today, future measurements might also assess the deformation of Earth-sized exoplanets. Moreover, the measurements of thermal emission light curves, accessible to JWST [4], might shed light on the actual spin states of low-mass exoplanets, which is another parameter affecting the long-term evolution and the habitability prospects of the extrasolar worlds. Detailed analysis of the light curves can also unveil global-scale volcanism that would be indicative of the magnitude of tidal dissipation [5].

Here, we discuss and illustrate the link between various aspects of the planet’s interior structure and a set of potential observables related to tides on close-in rocky exoplanets without atmosphere. Specifically, we focus on the role of different rheological models and their parameters and on the major features of the interior structure, such as liquid layers or low-viscosity zones. We address the stability of various spin-orbit resonances, surface tidal heat flux, the magnitude of the tidal Love numbers h2 and k2, and the present-day effect of tides on the orbital elements. Since the tidal deformation and the rate of energy dissipation in close-in rocky exoplanets also govern the secular orbital evolution, we further discuss the effect of changes in the interior structure, induced by variations in the thermal state, on the long-term orbital dynamics of tidally loaded exoplanets or moons [6].

 

Acknowledgement:

The work presented in this contribution has been supported by the Czech Science Foundation grant nr. 23-06513I.

 

References:

[1] Baumeister & Tosi (2023), doi:10.1051/0004-6361/202346216.

[2] Barros et al. (2022), doi:10.1051/0004-6361/202142196.

[3] Barker et al. (2024), doi:10.1093/mnras/stad3530.

[4] Zieba et al. (2023), doi:10.1038/s41586-023-06232-z.

[5] Selsis et al. (2013), doi: 10.1051/0004-6361/201321661.

[6] Walterová & Běhounková (2020), doi:10.3847/1538-4357/aba8a5.

How to cite: Walterová, M. and Běhounková, M.: Linking the interior structure of terrestrial exoplanets to their (tidal) observables, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16760, https://doi.org/10.5194/egusphere-egu24-16760, 2024.

X3.112
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EGU24-19574
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ECS
High-resolution exploration of transiting sub-Neptunes’ atmospheres with NIRPS
(withdrawn)
Dany Mounzer, Christophe Lovis, and Romain Allart
X3.113
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EGU24-18914
Nicolas Iro, Thomas Fauchez, Thaddeus Komacek, Emily Rauscher, and Lucas Teinturier

With the first exoplanet JWST and Cheops data available, and ARIEL in the near future, we are expecting to get a lot of time-varying measurements of exoplanets (e.g. phase curves and 3D eclipse maps), giving us unprecedented information about their climate. Hot Jupiters will be the best targets for  atmosphere characterisation with these facilities.

 

3D atmospheric circulation models are the main tools to interpret theoretically these upcoming observations, however, it is overwhelming to compare the numerous models developed independently with each various assumptions and setup. Some characteristics of their outputs are then dependent on the model used, impairing physical interpretation. It is therefore necessary to assess the differences, limits and applicability of each models in a controlled manner.

 

We present MOCHA (Modelling the Circulation of Hot exoplanet Atmospheres), the most extensive intercomparision of hot Jupiter 3D circulation models. Our team is built from the experts developing all available codes,  in order to set up a common benchmark methodology.

Our intercomparison project will provide the exoplanet community with protocols and methods to benchmark current and future 3D models. This will lead to better and more robust tools to retrieve physical information from JWST, Cheops, and later ARIEL data.

 

This project is part of CUISINES (Climates Using Interactive Suites of Intercomparisons Nested for Exoplanet Studies), which has already provided Model Intercomparisons Projects (MIPS) such as THAI for the TRAPPIST planets and CAMEMBERT for mini Neptunes.

How to cite: Iro, N., Fauchez, T., Komacek, T., Rauscher, E., and Teinturier, L.: Modelling the Circulation of Hot exoplanet Atmospheres (MOCHA): exhaustive comparison of 3D models for hot Jupiters, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18914, https://doi.org/10.5194/egusphere-egu24-18914, 2024.

X3.114
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EGU24-19056
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ECS
Fabian Seidler and Paolo Sossi

An essential aspect of understanding how rocky (exo-)planets form and evolve is unravelling their bulk composition. While mass and radius alone do not yield precise estimations of exoplanet compositions due to the degeneracy of interior models that can fit such observations, abundances of refractory elements in their host stars are often used as proxies to constrain terrestrial planet composition. However, oxygen, whose relative abundance governs how iron (and other siderophile elements) partition between the mantle and core, is both a volatile and a refractory element, preventing a straightforward determination from stellar abundances. Therefore, we require independent means to estimate exoplanet oxidation states through observations of their atmospheres and/or surfaces. To do so, observations of ultra-hot rocky exoplanets would be ideal, owing to the fact that their atmospheres are expected to be in thermodynamic equilibrium with their surfaces. To interpret such observations, we investigate the impact of oxygen fugacity (fO2), temperature (T) and composition on the formation of atmospheres on ultra-hot rocky exoplanets. Our approach treats melt vaporisation and atmospheric gas speciation thermodynamically self-consistently, before using radiative transfer simulations to predict atmospheric structure and emission spectra. We find that compositional effects are minor within the range of plausible rocky compositions. However, the emission spectrum is particularly sensitive to fO2, owing to its influence on the partial pressures of gas species in equilibrium with the silicate mantle. This effect is exacerbated when the atmosphere contains a volatile component such as H2O, CO2 or N2. We show that observations made with the James Webb Space Telescope (JWST) hold the potential to distinguish between fO2 scenarios, thereby paving the way for the first independent constraints on the chemistry of rocky exoplanets.

How to cite: Seidler, F. and Sossi, P.: Impact of oxygen fugacity on atmospheric spectra of hot rocky exoplanets, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19056, https://doi.org/10.5194/egusphere-egu24-19056, 2024.

X3.115
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EGU24-16195
Gabriel Tobie, Mathilde Kervazo, Yann Musseau, Marie Behounkova, Emeline Bolmont, Gael Choblet, Caroline Dumoulin, Alexandre Revol, and Mariana Villamil Sastre

The number of detected Earth-sized exoplanets is now increasing, and most of the detected planets orbit at relatively close distance from their host stars, resulting in strong tidal forcing. As shown for the inner planets of the Trappist-1 system [1] or the newly discovered Earth-sized exoplanet LP 791-18d [2], tidal heating is expected to be a dominant source of heating, potentially exceeding the radiogenic power by one order of magnitude and more. Depending on the orbital eccentricity, tidally-induced thermal runaways may result in strong internal melting and volcanic heat flux comparable to Io [3]. As shown in the case of Io, the presence of silicate melt in the interior of Io has a strong influence on the tidal response of its interior [3,4]. The thickness and melt content of partially molten layer can strongly affect the total dissipated power and its distribution.

In this study, we test the influence of partially molten layers on the tidal response of Earth-sized exoplanets, using Trappist-1 b,c and d and LP 791-18d as examples.  We follow the approach developed to model the solid tides in Io’s partially molten interior [3], taking into account the effect of melt on the viscoelastic properties of the mantle, and test different rheological models (Maxwell, Andrade, Sundberg-Cooper). We use interior structure models consistent with the estimated mass and radius and consider partially molten layers of various thickness,  depth and melt content. Results for various assumptions in interior composition and melt content will be presented and implications for the heat budget of these planets  will be discussed.

[1] Turbet et al. A&A 612, A86;  [2] Peterson et al.  Nature, 617, 701–705 (2023);  [3] Běhounková et al. ApJ, 728(2), 89 (2011) ; [4] Kervazo et al., A&A, 650, A72 (2021) ;  [5] Kervazo et al. Icarus, 373, 114737 (2022).

 

How to cite: Tobie, G., Kervazo, M., Musseau, Y., Behounkova, M., Bolmont, E., Choblet, G., Dumoulin, C., Revol, A., and Villamil Sastre, M.: Influence of partially molten layers on the tidal response of rocky exoplanets , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16195, https://doi.org/10.5194/egusphere-egu24-16195, 2024.

X3.116
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EGU24-20474
CAMEMBERT: A Mini-Neptunes General Circulation Model Intercomparison
(withdrawn)
Duncan Christie, Aaron Schneider, Benjamin Charnay, Denis Sergeev, Elspeth Lee, Emily Rauscher, Hamish Innes, Isaac Malsky, Ludmila Carone, Maria Steinrueck, Maria Zamyatina, Michael Roman, Nathan Mayne, Pascal Noti, Russell Deitrick, Thomas Fauchez, Thaddeus Komacek, and Justin Chen
X3.117
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EGU24-143
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ECS
Sabin Roman

We propose a formula for computing the average planetary surface temperatures based solely on the solar irradiance and the bond albedo. The formula is empirically derived from data on Earth, Venus and Titan, and a model is proposed to justify it. We introduce the concept of planetary inner albedo, as a complement to the usual bond albedo. A geometric proof is given for the main finding of the paper, which can be summarized as follows: the ratio of the inner to outer albedo is a constant, related to the universal parabolic constant. Furthermore, we extend the surface temperature formula to gas giants, giving the temperature at which condensates (e.g., of ammonia) start forming within their atmosphere, particularly for Jupiter, Saturn and Uranus. Based on model complexity, applicability and accuracy, the heating mechanism via atmospheric reflectivity (a mirror effect) performs much better than the alternatives.

How to cite: Roman, S.: Geometric considerations on planetary surface temperatures, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-143, https://doi.org/10.5194/egusphere-egu24-143, 2024.

Posters virtual: Thu, 18 Apr, 14:00–15:45 | vHall X3

Display time: Thu, 18 Apr, 08:30–Thu, 18 Apr, 18:00
Chairpersons: Maggie Thompson, Aurélien Falco
vX3.17
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EGU24-6296
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ECS
Nino Greco and Marco Montalto and the The GAPS Programme at TNG: TOI-5076b.

Aims. We report the confirmation of a new transiting exoplanet orbiting the star TOI-5076.
Methods. We present our vetting procedure and follow-up observations which led to the confirmation of the exoplanet TOI-5076b. In particular, we employed high precision TESS photometry, high-angular resolution imaging from several telescopes and high precision radial velocities from HARPS-N.
Results. From the HARPS-N spectroscopy, we determined the spectroscopic parameters of the host star: Teff=(5070±143) K, log g=(4.6±0.3), [Fe/H]=(+0.20±0.08) and [α/Fe]=0.05±0.06. The transiting planet is a warm sub-Neptune with a mass mp=(16±2) M, a radius rp=(3.2±0.1) R yielding a density ρp=(2.8±0.5) g cm−3. It revolves around its star every ∼23.445 days.
Conclusions. The host star is a metal-rich, K2V dwarf, located at about 82 pc from the Sun with a radius of R=(0.78±0.01) R and a mass of M=(0.80±0.07) M. It forms a common proper motion pair with a M-dwarf companion star located at a projected separation of 2178 au. The chemical analysis of the host-star and the Galactic space velocities indicate that TOI-5076 belongs to the old population of thick disk stars or thin-to-thick transition stars. The density of TOI-5076b suggests the presence of a large fraction by volume of volatiles overlying a massive core. We found that a circular orbit solution is only marginally favoured with respect to an eccentric orbit solution for TOI-5076b. The best-fit eccentricity for the system is e=(0.20±0.09).

How to cite: Greco, N. and Montalto, M. and the The GAPS Programme at TNG: TOI-5076b.: The GAPS Programme at TNG. TOI-5076b: a warm sub-Neptune planet orbiting a thick disk star in a wide binary system., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6296, https://doi.org/10.5194/egusphere-egu24-6296, 2024.