arXiv subjects

Yamila Miguel

Publications and source records attributed to Yamila Miguel.

At least 19 recordsLinked to original sources

arXiv2026

Can the Long-Term Impact of Stellar M-Dwarf Flares Alter the Spectral Features of a Giant Gaseous Exoplanet?

In this work, we model the long-term impact of recurrent stellar flares on the atmospheres of metal-rich gaseous exoplanets. Using synthetic flare spectra from a fiducial flare model integrated with a photochemical kinetics code, we track the changes in atmospheric composition with time. We further analyze the spectral variability by feeding these abundance profiles into a radiative transfer code at various time steps. Our simulations showed variability and persistent changes in key atmospheric species, such as CH4, CO2, and SO2, when compared to their quiescent state. Extreme flare events cause rapid depletion of molecules in the upper atmosphere and a temporary disappearance of spectral features, especially the SO2 feature at 7-8 microns, which shifted by about 75 ppm. Many species did not fully return to their quiescent state after flares, resulting in lasting changes in abundance, especially for SO2 and CO2, key species when inferring the atmospheric metallicty. We also explored the cumulative effects of recurrent flares, showing that species like H2O and CH4 followed a decreasing abundance trend, with half-lives of around 28 to 31 years. These results indicate that flare activity plays a significant role in shaping both the short- and long-term atmospheric composition and spectral features of giant gaseous exoplanets orbiting M-dwarf stars, underscoring the need to account for stellar activity when characterising such atmospheres. Our findings also highlight that the atmosphere of the modelled planet is not static, suggesting that a probabilistic approach to atmospheric abundances may be more appropriate than static retrievals, particularly for gaseous planets orbiting active stars.

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arXiv2026

The effect of the atmospheric C/O ratio on interiors of hot Jupiters

The atmosphere is the outer boundary of a gas giant exoplanet's interior. Therefore, compositional changes in the atmosphere can affect interior inferences. Typically, only metallicity is considered in atmospheric boundary conditions, while other elemental ratios, in particular the C/O ratio, are assumed to be solar. In light of the observational constraints now achievable with JWST, this assumption might no longer be justified. In this work, we investigate the effect of the C/O ratio on atmospheric boundary conditions, interiors and radii of hot Jupiters. We construct an atmospheric boundary grid, consisting of one-dimensional atmospheric models in radiative-convective and thermochemical equilibrium. This grid is coupled to a static interior structure model at the radiative-convective boundary (RCB). Because in the temperature regime of hot Jupiters, the C/O ratio determines the dominant species in the atmosphere, it can significantly alter the opacity and, consequently, the pressure and temperature at the RCB. This temperature change propagates into the convective interior, thus affecting the calculated radius. The radius difference relative to a solar C/O-atmosphere significantly exceeds observed radius uncertainties of 3 per cent for planets with equilibrium temperatures $\gtrsim$ 1500 K and super-solar atmospheric metallicities. As an example, we demonstrate that, for WASP-19~b, higher C/O ratios result in higher inferred intrinsic temperatures. These results highlight the importance of treating atmospheric composition and interior structure as a coupled system. As atmospheric constraints improve, incorporating measured C/O ratios into atmospheric boundary conditions is necessary to obtain robust inferences of hot Jupiter interiors.

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arXiv2026

Alkali lines at extreme densities and their impact on giant planet interior structure

Alkali lines, in particular the sodium Na $D$ (5891$\AA$, 5897$\AA$) and potassium K $D$ (7667$\AA$, 7701$\AA$) resonance doublets, are dominant opacity sources in giant planets over a wide range of temperatures ($\gtrsim$1000K). Their strong pressure-broadened wings significantly influence the thermal structure of giant planets, especially at high pressures. Most detailed line-profile calculations have so far been limited to perturber densities up to $10^{21}$cm$^{-3}$. However, conditions in the deep atmospheres and interiors of giant planets can reach significantly higher densities, making the temperature gradients increasingly uncertain. We determined how physically consistent collisional broadening of the Na $D$ and K $D$ lines at extreme densities affects opacity calculations and consequently the inferred interior structure of giant planets. We computed detailed Na $D$ and K $D$ line profiles using unified line theory, extending to molecular hydrogen perturber densities of $n_{\rm H_2} = 5 \times 10^{22}$cm$^{-3}$, which translates to pressures up to $\sim$ 20kbar. The revised cross sections were incorporated into Rosseland mean opacity tables, which were then used to evaluate their effect on planetary thermal structures. At densities $n_{\rm H_2} > 10^{21}$cm$^{-3}$, the line profiles predicted by unified line theory exhibit significantly stronger wings than commonly used Voigt profiles, as well as density-dependent line shifts, which substantially increases Rosseland mean opacities. Consequently, the radiative-convective boundary of warm and hot giant planets can shift to lower pressures, producing warmer interior adiabats and increasing inferred core masses. We further find that Jupiter is unlikely to host a stable radiative layer at the present time or throughout most of its evolution, as the required Na and K abundances for this are well below observational constraints.

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arXiv2026

Implications of a Stable Layer on the Vertical Structure of Jet Streams on Jupiter

The vertical structure of Jupiter's jet streams remains a critical open question for understanding the planet's atmospheric dynamics and interior. Traditional models often assume an adiabatic density profile, yet recent observations and theory suggest the presence of stable layers, which could significantly alter both the density structure and gravitational signature. We investigate the implications of non-adiabatic stable layers for Jupiter's gravity field, focusing on how density anomalies from such layers interact with the inferred vertical structure of zonal winds. We construct temperature-pressure profiles including subadiabatic stable layers to derive density profiles consistent with the latest equation of state. The resulting gravitational harmonics are computed, incorporating both static density and wind structure via thermal wind balance, and compared with Juno measurements. By varying the wind decay characteristics, we assess how stable layers constrain the depth and structure of the deep jets. Our results show that shallow, extensive stable layers substantially modify the background density, requiring more rapid decay of zonal winds to satisfy observed gravitational constraints. Introducing stable layers also broadens the range of physically plausible wind solutions, inadicating that the vertical structure of the jets is less constrained than suggested by purely adiabatic models. We conclude that stable layers are a critical, yet often overlooked, component in modeling Jupiter's interior and dynamics. This study highlights a strong degeneracy between the thermodynamic density structure and the vertical wind profile, implying that the jet stream structure cannot be uniquely determined without independent constraints on the planet's internal stability.

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arXiv2026

Coupled atmospHere Interior modeL Intercomparison (CHILI). I. Evolutionary Modelling -- Primordial Magma Oceans of Earth and Venus

Earth and Venus represent two evolutionary outcomes arising from initially molten 'magma ocean' periods, followed by lifetimes of chemical and geophysical divergence. Their physics is common to all rocky planets and is accessible to simulations that adopt coupled interior-atmosphere modelling approaches. Our understanding of planet histories and interpretation of current states is dependent on this modelling, yet existing codes vary in their approximations. Here, we present the first results from the Coupled atmospHere Interior modeL Intercomparison (CHILI) project; benchmarking planetary evolution codes in the context of Earth and Venus to identify key model sensitivities. Our 'nominal' Earth models predict magma ocean solidification timescales within 4 Myr of thermal evolution, and are consistent with empirical constraints on Earth's early history. Venus scenarios exhibit more diverse behaviours where prolonged magma ocean stages can be conditionally sustained for 50 Myr. Cooling timescales correlate with initial hydrogen and carbon budgets, but model-specific treatments of volatile partitioning and vertical energy transport introduce substantial inter-model variance. Different parametrisations of mantle geodynamics, convection, melting curves, rheological properties, and radiative transfer give rise to divergent evolutionary behaviours. Discrepancies in atmospheres generated by magma ocean outgassing underscore these differences, although C-H-O compositions with surface pressures exceeding 100 bar are favoured. This intercomparison identifies critical sensitivities in volatile partitioning, escape processes, mantle viscosity, and melting. Validating these treatments is essential for enabling deep insight into the early histories of the Solar System's terrestrial planets, and for drawing meaningful interpretations from ongoing observational exoplanet campaigns.

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arXiv2026

Strong and variable stratospheric CO emission from lava-planet 55 Cnc e observed with NIRCam/JWST

Some rocky planets orbit so close to their host stars that stellar heating melts their surfaces. They offer a rare glimpse of planets in a magma-ocean state, providing an observable analogue to processes that likely shaped the early Earth and other terrestrial planets during their infancy. Recent JWST observations of five eclipses of the prototypical lava planet 55 Cnc e have confirmed earlier hints that it exhibits highly variable thermal emission, with low-resolution spectroscopy pointing to a possible volatile-rich atmosphere likely rich in CO and CO2. Here we report on an analysis of the same JWST datasets but at their native spectral resolution, utilizing cross-correlation techniques. An unambiguously strong ~8 sigma signal from CO in emission is recovered during one out of five epochs, with potential ~3 sigma detections during two others. The strongest observed cross-correlation signal is difficult to reconcile with a hydrostatic atmosphere, requiring a steep and strong thermal inversion at the right pressure level (~1-10 mbar) and a relative abundance of CO2 that is at least 3 orders of magnitude lower which would otherwise mask the CO signal. Self-consistent atmospheric modelling indicates that this is most readily achieved in a hydrogen-rich atmosphere, which produces the steepest inversions and highest CO/CO2 ratios. The pronounced epoch-to-epoch variability suggests that the CO signal does not trace a static atmosphere alone, but may reveal a transient, dynamically active component, potentially linked to variable atmospheric outflow.

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arXiv2026

Sensitivity of Dry Lava Planet Atmospheric Emission Spectra to Changes in Lava Compositions

The atmospheres of hot rocky exoplanets are among the first primary targets of the JWST. Interpreting their atmospheric spectra requires understanding the link between silicate lava compositions and overlying atmospheres. We investigate the sensitivity of simulated emission spectra of dry lava planets to variations in oxide abundances in silicate melt. Our goal is to determine which molten surface features could be distinguishable with future observations. We combine our vaporisation code with gas chemical equilibrium and radiative transfer codes to self-consistently compute atmospheric chemistry and thermal structure. Alongside varying lava compositions, we assess the impact of host star spectral type on emission spectra. TiO2 melt abundance dictates atmospheric TiO, which strongly influences surface temperature and emission spectra due to its short-wave opacity. This creates a degeneracy with heat redistribution efficiency, potentially broken by observing the optical TiO emission feature. Atmospheric SiO and SiO2 abundances depend on melt SiO2 content, with stronger SiO and SiO2 emission features at higher melt abundances. For the currently best observable HREs, changes in TiO2 and SiO2 abundance of about an order of magnitude with respect to BSE, could potentially be observable with 12 JWST eclipse observations.

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arXiv2026

Reassessing planetary composition: Evidence of rock-dominated envelopes in Uranus and Neptune

Although Uranus and Neptune are commonly classified as ice giants, their exact compositions remain poorly constrained. Recent studies of outer Solar System bodies challenge the traditional view that these planets are primarily ice-dominated, suggesting that refractory material plays a more significant role. Determining the proportions of ice and rock within Uranus and Neptune is essential for understanding their formation and the evolutionary history of the Solar System. In this work we computed interior structure models for both planets and explored, within a Bayesian framework, the range of compositions that satisfy the available observational constraints. We quantified the resulting ice and rock fractions and analyzed their impact on the inferred internal structure. Our results suggest that the envelopes of both Uranus and Neptune are systematically enriched in refractory material, with median rock fractions of approximately 60% within the heavy-element component, similar to Pluto, Kuiper belt objects, and comets. In contrast, the deep interiors of the two planets exhibit distinct compositions: Neptune is best fit by relatively rock-rich mantles (median rock fraction of ~ 55%), whereas Uranus is inferred to have more ice-rich mantles (median rock fraction of ~ 41%), consistent with a more strongly stratified structure. These results point to compositional differences between Uranus and Neptune that may reflect divergent formation and evolutionary pathways.

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arXiv2026

Coupled atmospHere Interior modeL Intercomparison (CHILI) Protocol Version 1.0: A CUISINES Intercomparison Project of Magma Ocean Models

Spectroscopic characterization of rocky exoplanets with the James Webb Space Telescope has brought the origin and evolution of their atmospheres into the focus of exoplanet science. Time-evolved models of the feedback between interior and atmosphere are critical to predict and interpret these observations and link them to the Solar System terrestrial planets. However, models differ in methodologies and input data, which can lead to significant differences in interpretation. In this paper, we present the experimental protocol of the Coupled atmospHere Interior modeL Intercomparison (CHILI) project. CHILI is an (exo-)planet model intercomparison project within the Climates Using Interactive Suites of Intercomparisons Nested for Exoplanet Studies (CUISINES) framework, which aims to support a diverse set of multi-model intercomparison projects in the exoplanet community. The present protocol includes the initial set of participating magma ocean models, divided into evolutionary and static models, and two types of test categories, one focused on Solar System planets (Earth & Venus) and the other on exoplanets orbiting low-mass M-dwarfs. Both test categories aim to quantify the evolution of key markers of the links between planetary atmospheres and interiors over geological timescales. The proposed tests would allow us to quantify and compare the differences between coupled atmosphere-interior models used by the exoplanet and planetary science communities. Results from the proposed tests will be published in dedicated follow-up papers. To encourage the community to join this comparison effort and as an example, we present initial test results for the early Earth and TRAPPIST-1 b, conducted with models differing in the treatment of energy transport in the planetary interior and atmosphere, surface boundary layer, geochemistry, and the in- and outgassing of volatile compounds.

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arXiv2026

On the synergetic use of Ariel and JWST for exoplanet atmospheric science

This paper explores the potential for strategic synergies between the JWST and the Ariel telescopes, two flagship observatories poised to revolutionise the study of exoplanet atmospheres. Both telescopes have the potential to address common fundamental questions about exoplanets-especially concerning their nature and origins-and serve a growing scientific community. With their operations now anticipated to overlap, starting from 2030, there is a unique opportunity to enhance the scientific outputs of both observatories through coordinated efforts. In this report, authored by the Ariel-JWST Synergy Working Group, part of the Ariel Consortium Science Team, we summarise the capabilities of JWST and Ariel; we highlight their key differences, similarities, synergies, and distinctive strengths. Ariel is designed to conduct a broad survey of exoplanet atmospheres but remains highly flexible, allowing the mission to integrate insights from JWST's discoveries. Findings from JWST, including data from initiatives shaped by NASA's decadal survey priorities and community-driven research themes, will inform the development of Ariel's core survey strategy. Conversely, Ariel's ability to perform broad-wavelength coverage observations for bright targets provides complementary avenues for exoplanet researchers, particularly those interested in time-domain observations and large-scale atmospheric studies. This paper identifies key pathways for fostering JWST-Ariel synergies, many of which can be initiated even before Ariel's launch. Leveraging their complementary designs and scopes, JWST and Ariel can jointly address fundamental questions about the nature, formation, and evolution of exoplanets. Such strategic collaboration has the potential to maximise the scientific returns of both observatories and lay the foundation for future facilities in the roadmap to exoplanet exploration.

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arXiv2026

Hot and cloudy: High temperature clouds in super-Earths and sub-Neptunes

JWST observations provide for the first time evidence for an atmosphere on a rocky exoplanet - 55 Cnc e. The atmosphere of 55 Cnc e is hot with $\text{T}_{\text{eq}}>2000$K and shows strong variability, for which cloud formation above a molten crust could be one possible explanation. The composition of the atmosphere of 55 Cnc e is still unknown but suggests the presence of volatiles. We have run cloud formation models on a grid of N-dominated, O-dominated, C-dominated and H-dominated atmospheres to investigate which type of cloud we could expect on hot super-Earths and hot sub-Neptunes ($1000$K $<$ T $<$ $3000$K). Our models combine radiative transfer with equilibrium chemistry of the gaseous and condensed phases, vertical mixing of condensable species, sedimentation, nucleation and coagulation. We find that the condensability of species is highly dependent on the oxygen abundance of an atmosphere. Oxygen poor atmospheres can be heated by UV and optical absorbers PS, TiO and CN which create temperature inversions. These inhibit condensation. Oxygen rich atmospheres are colder without temperature inversions, and are therefore more favourable environments for cloud formation. The major expected cloud component in O-dominated atmospheres with solar refractory abundance is TiO$_2$(s). Spectral features of clouds in these worlds are stronger in transmission than in emission, in particular at short wavelengths. We find a lack of optical data of solid species in comparison to the variety of stable cloud components which can form on hot, rocky planets.

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arXiv2026

Investigating the High-energy Radiation Environment of Planets in Sun-like Binary Systems

Far-ultraviolet (FUV) radiation is a driving source of photochemistry in planetary atmospheres. Proper interpretation of atmospheric observations requires a full understanding of the radiation environment that a planet is exposed to. Using the Suborbital Imaging Spectrograph for Transition-region Irradiance from Nearby Exoplanet host stars (SISTINE) rocket-borne spectrograph, we observed the Sun-like binary system $α$ Centauri AB and captured the FUV spectrum of both stars simultaneously. Our spectra cover 980--1570 Å, providing the broadest FUV wavelength coverage taken in a single exposure and spanning several key stellar emission features which are important photochemical drivers. Combining the SISTINE spectrum with archival observations, model spectra, and a novel stellar activity model, we have created spectral energy distributions (SEDs) spanning 5 Å--1 mm for both $α$ Centauri A and B. We use the SEDs to estimate the total high-energy flux (X-ray--UV) incident on a hypothetical exoplanet orbiting $α$ Centauri A. Because the incident flux varies over time due to the orbit of the stellar companion and the activity level of each star, we use the VULCAN photochemical kinetics code to estimate atmospheric chemical abundances in the case of minimum and maximum flux exposure. Our results indicate that enhanced atmospheric mass loss due to stellar binarity will likely not be an issue for future exoplanet-hunting missions such as the Habitable Worlds Observatory when searching for Earth-like planets around Sun-like stars.

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arXiv2026

Mean opacity tables for probing the interior and atmosphere of giant planets

We present new Rosseland and Planck mean opacity tables relevant to the shallow interiors and atmospheres of giant planets. The tables span metallicities from 0.31 to 50 times solar, temperatures from 100 - 6000 K, and pressures from 1e-6 - 1e5 bar, thereby covering a wider parameter space than previous data sets. Our calculations employ the latest molecular and atomic line lists and pressure-broadening treatments, and include contributions from collision-induced absorption, free electrons, and scattering processes. We further provide cloudy mean opacity tables that account for cloud particle extinction across a range of particle sizes and capture the sequential removal of condensates as the gas cools. We benchmark our cloud-free tables against widely used opacity tables and find significant relative differences, exceeding 100% in Rosseland mean opacities at T \gtrsim 3000 K due to the inclusion of additional short-wavelength absorbers. Differences in Planck mean opacities at high temperatures are even larger, in some cases exceeding two orders of magnitude, which is most likely driven by the inclusion of Ca, Mg, and Fe cross-sections and updated Na D and K I resonance line treatments. Cloud opacities substantially increase Rosseland mean opacities for T \lesssim 2800 K, while their effect on Planck mean opacities is weaker. We also discuss limitations of our mean opacities at high pressures, where non-ideal effects become important. This work provides improved cloud-free mean opacity tables for giant planets, as well as the first publicly available cloudy mean opacity tables, which will enable more realistic modeling of their atmospheres and interiors.

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arXiv2026

The MUSCLES Extension for Atmospheric Transmission Spectroscopy: Spectral energy distributions for 20 exoplanet host stars that JWST observed in Cycle 1

Correctly interpreting JWST spectra of close-in exoplanets requires a measurement of the X-ray and ultraviolet light that the planets receive from their host stars. Here we provide spectral energy distributions (SEDs) covering the range $\approx5-1\times10^7$A for 20 transiting exoplanet host stars observed in JWST Cycle 1. The SEDs are constructed out of new and archival Hubble Space Telescope, Chandra X-ray Observatory and/or XMM-Newton data combined with spectra from models or stars with similar properties (proxies) filling in unobserved gaps. We have also constructed SEDs of likely Habitable Worlds Observatory targets $κ^1$ Ceti, $τ$ Ceti, $ε$ Indi and 70 Oph B for use as proxies. We find that the JWST target planets almost all experience much stronger ultraviolet fluxes than the Earth, especially in the extreme ultraviolet, even for planets with similar overall instellation. Strong ongoing or past atmospheric escape is possible for a majority of these planets. We also assess the now considerable sample of panchromatic stellar SEDs and its applicability for current JWST observations and beyond.

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arXiv2025

Formation of cold giant planets around late M dwarfs via core accretion and the fate of inner rocky worlds

Modeling the formation of cold giant planets around M dwarfs is difficult because their disks may not contain enough solids to form massive cores and because forming giants are expected to migrate inward through disk interactions. It is also unclear whether inner rocky planets can survive in systems hosting a cold giant, with implications for the habitability of close-in worlds. We investigated the conditions that allow giant planets to form at 1-3 au around a 0.1 M$_\odot$ star and explored when a close-in rocky planet can survive. We perform N-body simulations in which embryos grow through pebble and gas accretion in a disk with a local turbulent viscosity of $α_t = 10^{-4}$. Planet-disk interactions are included using a prescription that triggers outward migration when the planet-to-star mass ratio ($q$) exceeds 0.002. We find that a cold giant can form even in a disk with an initial pebble mass of 6 M$_\oplus$ if the disk gas mass is 10$\%$ of the stellar mass. This requires a compact 20 au disk with a dense inner region set by $α_g = 10^{-4}$, the assembly of a $\sim$5 M$_\oplus$ core within 1 Myr, and a disk lifetime of 10 Myr. A close-in rocky planet can survive if it reaches the inner cavity before the outer body becomes a giant. Thus, giant planet formation around very low-mass stars does not require high dust masses as previously thought. A combination of planet-planet collisions, efficient pebble accretion, and a long disk lifetime plays a key role in enabling the formation of cold giant planets with masses between those of Saturn and Jupiter.

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arXiv2025

Possible Evidence for the Presence of Volatiles on the Warm Super-Earth TOI-270 b

The search for atmospheres on rocky exoplanets is a crucial step in understanding the processes driving atmosphere formation, retention, and loss. Past studies have revealed the existence of planets interior to the radius valley with densities lower than would be expected for pure-rock compositions, indicative of the presence of large volatile inventories which could facilitate atmosphere retention. Here we present an analysis of the JWST NIRSpec/G395H transmission spectrum of the warm ($T_\mathrm{eq,{A_B}=0}$ = 569 K) super-Earth TOI-270 b ($R_\mathrm{p}$ = 1.306 $R_\oplus$), captured alongside the transit of TOI-270 d. The JWST white light-curve transit depth updates TOI-270 b's density to $ρ_\mathrm{p}$ = 3.7 $\pm$ 0.5 g/cm$^3$, inconsistent at 4.4$σ$ with an Earth-like composition. Instead, the planet is best explained by a non-zero, percent-level water mass fraction, possibly residing on the surface or stored within the interior. The JWST transmission spectrum shows possible spectroscopic evidence for the presence of this water as part of an atmosphere on TOI-270 b, favoring a H$_2$O-rich steam atmosphere model over a flat spectrum ($\ln\mathcal{B}$ = $0.3-3.2$, inconclusive to moderate), with the exact significance depending on whether an offset parameter between the NIRSpec detectors is included. We leverage the transit of the twice-larger TOI-270 d crossing the stellar disk almost simultaneously to rule out the alternative hypothesis that the transit-light-source effect could have caused the water feature in TOI-270 b's observed transmission spectrum. Planetary evolution modeling furthermore shows that TOI-270 b could sustain a significant atmosphere on Gyr timescales, despite its high stellar irradiation, if it formed with a large initial volatile inventory.

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arXiv2025

Volcanic Satellites Tidally Venting Na, K, SO2 in Optical & Infrared Light

Recent infrared spectroscopy from the James Webb Space Telescope (JWST) has spurred analyses of common volcanic gases such as carbon dioxide (CO2), sulfur dioxide (SO2), alongside alkali metals sodium (Na I) and potassium (K I) surrounding the hot Saturn WASP-39 b. We report more than an order-of-magnitude of variability in the density of neutral Na, K, and SO2 between ground-based measurements and JWST, at distinct epochs, hinting at exogenic physical processes similar to those sourcing Io's extended atmosphere and torus. Tidally-heated volcanic satellite simulations sputtering gas into a cloud or toroid orbiting the planet, are able to reproduce the probed line-of-sight column density variations. The estimated SO2 flux is consistent with tidal gravitation predictions, with a Na/SO2 ratio far smaller than Io's. Although stable satellite orbits at this system are known to be < 15.3 hours, several high-resolution alkali Doppler shift observations are required to constrain a putative orbit. Due to the Roche limit interior to the planetary photosphere at ~ 8 hours, atmosphere-exosphere interactions are expected to be especially important at this system.

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arXiv2025

On Linking Planet Formation Models, Protoplanetary Disk Properties, and Mature Gas Giant Exoplanet Atmospheres

Measuring a single elemental ratio (e.g., carbon-to-oxygen) provides insufficient information for understanding the formation mechanisms and evolution that affect our observations of gas giant planet atmospheres. Although the fields of planet formation, protoplanetary disks, and exoplanets are well established and interconnected, our understanding of how to self-consistently and accurately link the theoretical and observational aspects of these fields together is lacking. To foster interdisciplinary conversations, the Max-Planck Institut für Astronomie (MPIA) hosted a week-long workshop called, "Challenge Accepted: Linking Planet Formation with Present-Day Atmospheres." Here, we summarize the latest theories and results in planet formation modeling, protoplanetary disk observations, and atmospheric observations of gas giant atmospheres to address one of the challenges of hosting interdisciplinary conferences: ensuring everyone is aware of the state-of-the-art results and technical language from each discipline represented. Additionally, we highlight key discussions held at the workshop. Our main conclusion is that it is unclear what the ideal observable is to make this link between formation scenarios and exoplanet atmospheres, whether it be multiple elemental abundance ratios, measuring refractory budgets, or something else. Based on discussions held throughout the workshop, we provide several key takeaways of what the workshop attendees feel need the most improvement and exploration within each discipline.

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