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Context. The formation and global spatial distribution of photochemically produced haze particles in exoplanet atmospheres remain key processes for understanding their observed properties. Aims. We aim to develop a flexible haze particle formation and evolution model suitable for time-dependent exoplanet atmosphere simulations. Methods. Inspired by recent 2D photochemical modelling efforts, we include a simple activation timescale mechanism in our model to emulate a delayed formation of solid haze particles. We couple our new microphysical haze formation scheme,mini-haze, to theExo-FMSgeneral circulation model and simulated an idealised HD 189733b case study to examine the 3D spatial distribution and sizes of haze particles. Results. Our results suggest that for our chosen haze formation efficiency, particles do not grow beyond ~30 nm, in line with previous detailed 1D modelling. We find the haze spatial distribution follows the vertical velocity structure of the atmosphere, with equatorial convergence patterns of material deeper in the atmosphere at ~10⁻²bar. The resulting global distribution leads to enhanced haze opacity in the east and west limbs of the atmosphere. In our test cases, radiative feedback from haze opacity can strongly affect the temperature-pressure structures in the upper atmosphere, depending on the production rate. Our synthetic spectra results suggest that longer haze-production timescales give rise to stronger haze opacity effects on the observed transmission spectra compared to short timescale dayside formation, but the stronger thermal feedback from nightside formation leads to an overall larger dayside emission flux. Conclusions. Our current simulations represent a step towards investigating self-consistent haze formation and evolution with chemical feedback effects in 3D and can be readily applied to other objects of interest, such as sub-Neptune atmospheres. 

Abstract The bulk elemental abundances of Jupiter provide critical insights into its formation history and interior structure. Recent observations by the Juno Microwave Radiometer (MWR) reveal a deep Jovian atmosphere significantly depleted in electrons, implying an alkali metal (Na, K) abundance of 10⁻¹–10⁻⁵× solar. This depletion stands in sharp contrast to the supersolar volatile enrichments measured by the Galileo probe. We propose that this apparent depletion arises from mineral cloud-induced processes deep in the atmosphere. We explore two physical mechanisms using thermochemical and microphysical modeling. In the “chemical sequestration” scenario, vigorous vertical mixing lofts deep refractory condensates (e.g., spinel) into the 1000–2000 bar region, where they react to form alkali feldspars (albite) and feldspathoids (leucite), efficiently sequestering gaseous Na and K. In the “dust-catalyzed recombination” scenario, the bulk alkali inventory remains gaseous, but the free electron density is suppressed by dust–plasma interactions. Thermally emitted alkali ions from the surfaces of micron-sized iron and silicate grains significantly increase the cation density, driving rapid recombination of free electrons. Both mechanisms allow for a bulk solar or even supersolar alkali inventory while suppressing the electron density to match Juno observations. Analyzing an extended dataset of MWR observations with 61 perijoves, we detect spatial variability in the deep atmosphere that suggests modulation by mineral clouds. Our findings challenge the traditional “rainout” framework, unveiling a deep “mineralogical zone” in Jupiter shaped by dynamics and heterogeneous chemistry, resembling the photospheres of hot exoplanets and brown dwarfs. 

Knowing the composition of Jupiter’s atmosphere is crucial for constraining Jupiter’s bulk metallicity and formation history. Yet, constraining Jupiter’s atmospheric water abundance is challenging due to its potential nonuniform distribution. Here, we explicitly resolve the water hydrological cycle in Jupiter’s midlatitudes using high-resolution simulations. Falling precipitation leads to a significant large-scale depletion of water vapor beneath the lifting condensation level. A nonuniform water vapor distribution emerges in the midlatitude simulation with a changing Coriolis parameter across latitudes and spatially uniform cooling and heating. Water abundance at the 7-bar level varies by up to a factor of ten across latitudes, from subsolar to supersolar values. We propose that nonlinear large-scale eddies and waves tend to drift air parcels across latitudes along constant potential vorticity (PV) surfaces, thereby sustaining latitudinal dependencies in water vapor and the interplay between water distribution and large-scale dynamics. Therefore, water distribution is influenced by the vertical structure of density stratification and changing Coriolis parameter across Jupiter’s midlatitudes, as quantified by PV. Additionally, the water hydrological cycle amplifies the specific energy of air parcels through the latent heat effect, thereby slowing down vertical mixing with a latent heat flux. The horizontal gradient of water is expected to be more pronounced with a supersolar water abundance. We suggest that similar interplays between precipitating condensates, planetary rotation, and distribution of condensable species generally exist in the weather layer of fast-rotating giant planets. The ongoing Juno mission and future Uranus mission may further reveal the nonuniform distribution of condensed species and their interplay with large-scale dynamics. 

We present a single-shot detection method of terahertz correlated second harmonic generation in plasma-based sources by directly mixing an optical probe into femtosecond laser-induced plasma filaments in air. The single-shot second harmonic trace is obtained by measuring a second harmonic generation on a conventional CCD with a spatiotemporally distorted probe beam. The system shows a spectrometer resolution of 22 fs/pixel on the CCD and a true resolution on the order of the probe pulse duration. With considerable THz peak electric field strength, this formalism can open the door to single-shot THz detection without bandwidth limitations. 

Abstract Recently, optically active spin defects embedded in two-dimensional (2D) van der Waals (vdW) crystals have emerged as a transformative quantum sensing platform to explore cutting-edge materials science. Taking advantage of excellent solid-state integrability, this new class of spin defects can be readily arranged in nanoscale proximity to target materials, showing great promise for realizing in-situ quantum sensing of microscopic spin and charge behaviors in vdW heterostructures. Here we report hexagonal boron nitride-based quantum imaging of field-free deterministic magnetic switching and electric current distributions in an all-vdW spin-orbit torque (SOT) system. By visualizing variations of nanoscale magnetic stray field profile of room-temperature 2D magnet Fe₃GaTe₂under different SOT conditions, we show how the magnetic switching evolves from deterministic to stochastic behavior due to the interplay between spin orientations, anisotropy and Joule heating. Micromagnetic simulations rationalize our results well, revealing the role of field-like SOT in inhibiting thermal fluctuation driven stochastic switching and chaotic multi-domain competition. This understanding, which is otherwise difficult to access by conventional transport measurements, offers valuable insights into material design, testing, and performance evaluation of next-generation vdW spintronic devices. 

Aerosols in Jupiter’s stratosphere form intriguing polar hoods, which have been investigated by ultraviolet cameras on Cassini and the Hubble Space Telescope. Transient, concentrated dark ovals of unknown origin have been noted within both the northern and southern polar hoods. However, a systematic comparative study of their properties, which could elucidate the physical processes active at the poles, has not yet been performed due to infrequent observations. Using 26 global maps of Jupiter taken by Hubble between 1994 and 2022, we detected transient ultraviolet-dark ovals with a 48% to 53% frequency of occurrence in the south. We found the southern dark oval to be 4 to 6 times more common than its northern counterpart. The southern feature is an anticyclonic vortex and remains within the auroral oval during most of its lifetime. The oval’s darkness is consistent with a 20 to 50 times increase in haze abundance or an overall upward shift in the stratospheric haze distribution. The anticyclonic vorticity of the dark oval is enhanced relative to its surroundings, which represents a deep extension of the higher-altitude vortices previously reported in the thermosphere and upper stratosphere. The haze enhancement is probably driven by magnetospheric momentum exchange, with enhanced aerosols producing the localized heating detected in previous infrared retrievals.