Related papers: Stellar space weather effects on potentially habit…
Energetic particles, in the form of stellar energetic particles and cosmic rays, can lead to disequilibrium chemical effects in exoplanetary atmospheres. In Earth-like atmospheres, energetic particles can drive the formation of prebiotic…
As part of the project Pathways to Habitability (http://path.univie.ac.at/), we study the properties of the stellar winds of low-mass and Sun-like stars, and their influences on the atmospheres of potentially habitable planets. For this…
Space weather plays an important role in the evolution of planetary atmospheres. Observations have shown that stellar flares emit energy in a wide energy range (10^30-10^38 ergs), a fraction of which lies in X-rays and extreme ultraviolet…
Proper characterization of the host star to a planet is a key element to the understanding of its overall properties. The star has a direct impact through the modification of the structure and evolution of the planet atmosphere by being the…
With more than 260 extrasolar planetary systems discovered to-date, the search for habitable planets has found new grounds. Unlike our solar system, the stars of many of these planets are hosts to eccentric or close-in giant bodies. Several…
Stellar magnetic activity, manifested through spots (faculae and flares), fundamentally shapes the exoplanets' environments. For low-mass stars in particular, where most habitable-zone planets reside, the variable magnetic phenomena can…
The Sun is an active star that can have a direct impact on the Earth, its magnetosphere, and the technological infrastructure on which modern society depends. Among the phenomena that drive "space weather" are fast solar wind streams and…
Planets orbiting young, solar-type stars are embedded in a more energetic environment than that of the solar neighbourhood. They experience harsher conditions due to enhanced stellar magnetic activity and wind shaping the secular evolution…
Temperate sub-Neptune exoplanets could contain large inventories of water in various phases, such as water-worlds with water-rich atmospheres or even oceans. Both space-based and ground-based observations have shown that many exoplanets…
X-rays and extreme ultraviolet radiation impacting on a gas produce a variety of effects that, depending on the electron content, may provide a significant heating of the illuminated region. In a planetary atmosphere of solar composition,…
The tidal heating of hypothetical rocky (or terrestrial) extra-solar planets spans a wide range of values depending on stellar masses and initial orbits. Tidal heating may be sufficiently large (in many cases, in excess of radiogenic…
Young stars show a variety of highly energetic phenomena, from accretion and outflow processes to hot coronal plasmas confined in their outer atmosphere, all regulated by the intense stellar magnetic fields. Many aspects on each of these…
In our own solar system, the necessity of understanding space weather is readily evident. Fortunately for Earth, our nearest stellar neighbor is relatively quiet, exhibiting activity levels several orders of magnitude lower than young,…
Stellar flares are a frequent occurrence on young low-mass stars around which many detected exoplanets orbit. Flares are energetic, impulsive events, and their impact on exoplanetary atmospheres needs to be taken into account when…
We examine the effects of the engulfment of planets by giant stars on the evolution of late-type stars. We show that the rate at which dynamo-generated magnetic energy is being released exceeds 10% of the wind kinetic energy when the…
By applying an one-dimensional aeronomic model of the upper atmosphere of the close-in giant planet HD 209458b, we study the reaction of the planetary atmosphere to an additional heating caused by the influence of a stellar flare. It is…
Atmospheric compositions for rocky exoplanets will depend strongly on the bulk planetary composition and the orbital position of the planet. Non-traditional gases may be present in the atmospheres of exceptionally hot planets. Atmospheres…
Exoplanetary science continues to excite and surprise with its rich diversity. We discuss here some key aspects potentially influencing the range of exoplanetary terrestrial-type atmospheres which could exist in nature. We are motivated by…
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…
When stars depart from the main-sequence, various changes occur including the loss of angular momentum owing to changes in the stellar interior and the impact of stellar winds. These processes affect the amount of outer atmospheric heating…