![Clouds may form via heterogeneous nucleation on top of ‘seed’ photochemical haze particles. Whether or not this pathway dominates over homogeneous nucleation—the process through which ‘pure’ clouds spontaneously form—depends on the microphysical contact angle between the relevant cloud and haze species. Smaller contact angles correspond to stronger cloud-haze interactions due to the increased affinity between the clouds and hazes. While this contact angle is unknown in the absence of lab data, heterogeneous nucleation is the primary cloud-formation pathway across the Solar System. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Wet-Removal.png?resize=1200%2C715&ssl=1)
[astro-ph.EP] Aerosols are a near-ubiquitous feature of sub-Neptune atmospheres, yet their microphysical nature remains poorly understood. Both condensate clouds and photochemical hazes have been proposed to explain observations, but have […]
aerosols
Posted inAnalog Studies, Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Cryobiology, Icy Worlds, Imaging & Spectroscopy, Status Report, Titan
Feeling the Pressure: Effects of Formation Pressure on the Physical Properties of Titan Haze Analogs
The Cassini-Huygens mission detected large negative ions in Titan’s ionosphere at pressures as low as 10−6 torr. These ions ultimately polymerize to form Titan’s complex organic haze particles, which are […]
Posted inAstrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Gas Giants, Imaging & Spectroscopy, Status Report, Titan, Venus
Measurement of Photochemical Haze Refractive Indices and Hygroscopicity: Influence of CO2 in CH4/H2S/N2 Mixtures
Atmospheric organic hazes are widespread across various planetary bodies and have significant effects on both the surface and atmosphere. In this study, we investigate the optical and hygroscopic properties of […]
Posted inAstronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Ice Giant, Icy Worlds, Imaging & Spectroscopy, Press Release, Uranus, Water/Hycean Worlds & Oceanography
20-Year Hubble Study of Uranus Yields New Atmospheric Insights
The ice-giant planet Uranus, which travels around the Sun tipped on its side, is a weird and mysterious world. Now, in an unprecedented study spanning two decades, researchers using NASA’s […]
Posted inAstrogeology, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Exploration Gear & Tech, Lava / magma ocean / Volcanic Worlds, Sample Return, Status Report, Venus
Venus Cloud Catcher As A Proof Of Concept Aerosol Collection Instrument
We report on the proof-of-concept of a low-mass, low-power method for collecting micron-sized sulfuric acid aerosols in bulk from the atmosphere of Venus. The collection method uses four wired meshes […]
Posted inAstronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report
Evidence for Morning-to-Evening Limb Asymmetry on the Cool Low-Density Exoplanet WASP-107b
Transmission spectroscopy has enabled unprecedented insights into the makeup of exoplanet atmospheres. A transmission spectrum combines contributions from a planet’s morning and evening limbs, but these limbs may have different […]
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Habitable Zones, Imaging & Spectroscopy, Mars, Status Report
Unambiguous Detection Of Mesospheric CO2 Clouds On Mars Using 2.7 μm Absorption Band From The ACS/TGO Solar Occultations
Mesospheric CO2 clouds are one of two types of carbon dioxide clouds known on Mars. We present observations of mesospheric CO2 clouds made by Atmospheric Chemistry Suit (ACS) onboard the […]
Posted inAstronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report
Constraints On Atmospheric Water Abundance and Cloud Deck Pressure in the Warm Neptune GJ 3470 b via CARMENES Transmission Spectroscopy
Observations of cooler atmospheres of super-Earths and Neptune sized objects often show flat transmission spectra.
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Mars, Status Report
Dynamical Phenomena In The Martian Atmosphere Through Mars Express Imaging
This review describes the dynamic phenomena in the atmosphere of Mars that are visible in images taken in the visual range through cloud formation and dust lifting.
Posted inArctic / Antarctic / Alpine, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Icy Worlds, Microbiology & Virology, Press Release
Biological Particles Play A Crucial Role In Arctic Cloud Ice Formation
An international team of scientists from Sweden, Norway, Japan, and Switzerland, has presented research findings that reveal a crucial role of biological particles, including pollen, spores, and bacteria, in the […]