相关论文: Atmospheric electrification in dusty, reactive gas…
Lightning is present in all solar system planets which form clouds in their atmospheres. Cloud formation outside our solar system is possible in objects with much higher temperatures than on Earth or on Jupiter: Brown dwarfs and giant…
The last few years has seen a dramatic increase in the number of exoplanets known and in the range of methods for characterising their atmospheric properties. At the same time, new discoveries of increasingly cooler brown dwarfs have pushed…
Brown dwarfs and giant gas extrasolar planets have cold atmospheres with a rich chemical compositions from which mineral cloud particles form. Their properties, like particle sizes and material composition, vary with height, and the mineral…
Atmospheric electrification is not a purely terrestrial phenomenon: all Solar System planetary atmospheres become slightly electrified by cosmic ray ionisation. There is evidence for lightning on Jupiter, Saturn, Uranus and Neptune, and it…
Electric discharges were detected directly in the cloudy atmospheres of Earth, Jupiter and Saturn, are debatable for Venus, and indirectly inferred for Neptune and Uranus in our solar system. Sprites (and other types of transient luminous…
Brown Dwarf and extrasolar planet atmospheres form clouds which strongly influence the local chemistry and physics. These clouds are globally neutral obeying dust-gas charge equilibrium which is, on short time scales, inconsistent with the…
Extrasolar planets appear in a chemical diversity unseen in our own solar system. Despite their atmospheres being cold, continuous and transient plasma processes do affect these atmosphere where clouds form with great efficiency. Clouds can…
The lowest-mass stars, brown dwarfs and extrasolar planets present challenges and opportunities for understanding dynamics and cloud formation processes in low-temperature atmospheres. For brown dwarfs, the formation, variation and rapid…
Brown dwarfs are commonly regarded as easily-observed templates for exoplanet studies, with comparable masses, physical sizes and atmospheric properties. There is indeed considerable overlap in the photospheric temperatures of the coldest…
Observations and models suggest that the conditions to develop lightning may be present in cloud-forming extrasolar planetary and brown dwarf atmospheres. Whether lightning on these objects is similar to or very different from what is known…
Mineral clouds in substellar atmospheres play a special role as a catalyst for a variety of charge processes. If clouds are charged, the surrounding environment becomes electrically activated, and ensembles of charged grains are…
The study of the composition of brown dwarf atmospheres helped to understand their formation and evolution. Similarly, the study of exoplanet atmospheres is expected to constrain their formation and evolutionary states. We use results from…
Clouds seem like an every-day experience. But -- do we know how clouds form on brown dwarfs and extra-solar planets? How do they look like? Can we see them? What are they composed of? Cloud formation is an old-fashioned but still…
Ground-based and spacecraft telescopic observations, combined with an intensive modeling effort, have greatly enhanced our understanding of hot giant planets and brown dwarfs over the past ten years. Although these objects are all fluid,…
The key to understanding an extrasolar giant planet's spectrum--and hence its detectability and evolution--lies with its atmosphere. Now that direct observations of thermal emission from extrasolar giant planets are in hand, atmosphere…
The characteristics of irradiated solar system planetary atmospheres have been studied for decades, consequently modern planetary science benefits from an exhaustive body of ground- and space-based data. The study of extrasolar planetary…
A planetary atmosphere is the outer gas layer of a planet. Besides its scientific significance among the first and most accessible planetary layers observed from space, it is closely connected with planetary formation and evolution, surface…
The terrestrial and gas-giant planets in our solar system may represent some prototypes for planets around other stars; the exoplanets because most stars have similar overall elemental abundances as our sun. The solar system planets…
Strong ionization on close-in extrasolar giant planets suggests that their atmospheres may be affected by ion drag and resistive heating arising from wind-driven electrodynamics. Recent models of ion drag on these planets, however, are…
Clouds also form in atmospheres of planets that orbit other stars than our Sun, in so-called extrasolar planets or exoplanets. Exoplanet atmospheres can be chemically extremely rich. Exoplanet clouds are therefor made of a mix of materials…