Sökning: "solar system: formation"

Visar resultat 1 - 5 av 67 avhandlingar innehållade orden solar system: formation.

  1. 1. The Formation of Giant Planets

    Författare :Michiel Lambrechts; Astronomi - Genomgår omorganisation; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Planet formation; Solar System; Exoplanets; Giant planets; Hydrodynamics;

    Sammanfattning : Giant planets form embedded in a protoplanetary disc around a young star. Close to the midplane a large fraction of the available mass in solids is found in particles of cm to dm in size, which drift towards the star due to friction with the surrounding gas. LÄS MER

  2. 2. Turbulence-Assisted Planetary Growth : Hydrodynamical Simulations of Accretion Disks and Planet Formation

    Författare :Wladimir Lyra; Nikolai Piskunov; Thomas Henning; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; accretion; accretion disks; hydrodynamics; instabilities; methods: numerical; solar system: formation; planets and satellites: formation; magnetohydrodynamics MHD ; turbulence; diffusion; stars: planetary systems: formation; Astronomy and astrophysics; Astronomi och astrofysik;

    Sammanfattning : The current paradigm in planet formation theory is developed around a hierarquical growth of solid bodies, from interstellar dust grains to rocky planetary cores. A particularly difficult phase in the process is the growth from meter-size boulders to planetary embryos of the size of our Moon or Mars. LÄS MER

  3. 3. Formation of solar bipolar regions : Magnetic flux concentrations from suction of the negative effective magnetic pressure instability

    Författare :Illa Rivero Losada; Axel Brandenburg; Matthias Rempel; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetohydrodynamics MHD ; turbulence; dynamo; Sun: magnetic fields; Sun: rotation; Sun: activity; Sun: dynamo; Astronomy; astronomi;

    Sammanfattning : Sunspots stand out on the visible solar surface. They appear as dark structures evolving and changing over time. They host energetic and violent events, like coronal mass ejections and flares, and concentrate strong magnetic fields. LÄS MER

  4. 4. The Dynamics of Star Cluster Formation

    Författare :Juan Pablo Farias Osses; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Star Cluster Formation; Star Formation; N-body simulations; Astronomy Astrophysics;

    Sammanfattning : How do star clusters form? We care, since these are the birth sites of most stars, perhaps including our own Sun. There are a great variety of different theoretical models of cluster formation and our main goal in this thesis is to examine the implications of these for the dynamical evolution of a cluster's stellar population, including the ejected stars. LÄS MER

  5. 5. Energy Transfer and Conversion in the Magnetosphere-Ionosphere System

    Författare :Lisa Rosenqvist; Stephan Buchert; Andris Vaivads; Mike Lockwood; Uppsala universitet; []
    Nyckelord :Space and plasma physics; solar system; space physics; magnetospheric physics; plasma physics; magnetic storms; substorms; boundary layers; magnetic reconnection; energy conversion; space weather; Rymd- och plasmafysik;

    Sammanfattning : Magnetized planets, such as Earth, are strongly influenced by the solar wind. The Sun is very dynamic, releasing varying amounts of energy, resulting in a fluctuating energy and momentum exchange between the solar wind and planetary magnetospheres. LÄS MER