Sökresultat

We know now that discs of gas and dust, so-called protoplanetary discs, form planets as side-products of the naturally occurring star formation process throughout the Milky Way. Young, growing planets in such discs are commonly referred to as protoplanets. In about 10\% of the so-far observed stars, this planet formation process leads to the occurrence of giant planets, such as Saturn, Jupiter, or

My talk is intended to stimulate discussions about methods in radiativetransfer for hydrodynamical model atmospheres of late-type stars. I willpresent a number a number of inherent problems, show how they arepresently tackled (if so), and ask for ideas for more efficient approaches.

AU Mic is a young planetary system with a resolved debris disc showing signs of planet formation and two transiting warm Neptunes near mean-motion resonances. Here we analyse three transits of AU Mic b observed with the CHaracterising ExOPlanet Satellite (CHEOPS), supplemented with sector 1 and 27 Transiting Exoplanet Survey Satellite (TESS) photometry, and the All-Sky Automated Survey from the gr

Chondrules are millimeter-sized spherules that dominate primitive meteorites (chondrites) originating from the asteroid belt. The incorporation of chondrules into asteroidal bodies must be an important step in planet formation, but the mechanism is not understood. We show that the main growth of asteroids can result from gas drag-assisted accretion of chondrules. The largest planetesimals of a pop

Hypervelocity stars (HVSs) are stars located in the Galactic halo travelling with extremely high speeds. They are produced when a binary approches the supermassive black hole (SMBH) in the Galactic Center (GC) and gets tidally broken up. In this process one of the stars is ejected with high velocity. The angle between the velocity of the incoming binary and the velocity of the ejected HVS is alm

In spectra obtained from foil-excited and laser-produced plasmas, we have identified 70 new lines as belonging to the spectra of fluorine-like scandium and vanadium ions, Sc XIII and V XV The new lines in the wavelength region from 70 to 600 Angstrom represent 2p(4)3s-3p, 3p-3d and 3d-4f transition arrays. The spectra have been interpreted with the aid of theoretical calculations, and the consiste

Measurements of dust coupled to the Jovian magnetosphere have been obtained with the dust detector on board the Galileo spacecraft. We report on data obtained during the first four orbits about Jupiter that had flybys of the Galilean satellites: Ganymede (orbits 1 and 2), Callisto (orbit 3), and Europa (orbit 4). The most prominent features observed are highly time variable dust streams recorded t

A small fraction of the halo field is made up of stars that share the light element (Z <= 13) anomalies characteristic of second generation globular cluster (GC) stars. The ejected stars shed light on the formation of the Galactic halo by tracing the dynamical history of the clusters, which are believed to have once been more massive. Some of these ejected stars are expected to show strong Al enha