Sökning: "planets and satellites: formation"

Hittade 5 avhandlingar innehållade orden planets and satellites: formation.

  1. 1. Formation and Early Evolution of Planetary Systems

    Författare :Daniel Carrera; Astronomi - Genomgår omorganisation; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; planet formation; planets and satellites: dynamical evolution and stability -- planets and satellites: gaseous planets -- planets and satellites: terrestrial planets; planets and satellites: terrestrial planets;

    Sammanfattning : Over the past 20 years we have discovered that exoplanets are common in the Galaxy, and are far more diverse than anyone expected. Half of all Sun-like stars are accompanied by at least one super-Earth (a planet with a size between Earth and Neptune), many planets have very high eccentricities indicative of a dynamical origin, and a small fraction of stars are accompanied by hot Jupiters, whose origin is poorly understood. LÄS MER

  3. 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

  4. 3. Formation of Pebble-Pile Planetesimals and the Interior Structure of Comets

    Författare :Karl Wahlberg Jansson; Astronomi - Genomgår omorganisation; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; planets and satellites: formation; minor planets; asteroids: general; comets: general;

    Sammanfattning : Planets form in protoplanetary discs of gas, dust and ice around newborn stars. In the Solar System, not only planets are found as a result from the time of planet formation, but also remnant planetesimals in the form of asteroids, Kuiper belt objects and comets. Recent observations, e.g. LÄS MER

  5. 4. Disentangling the Early History of the Solar System

    Författare :Simona Pirani; Astronomi - Genomgår omorganisation; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; planets and satellites: formation; planets and satellites: dynamical evolution and stability; Kuiper belt: general;

    Sammanfattning : Giant planets form out of a disc of gas and dust – called protoplanetary disc -- that surrounded the protosun at the time of its formation. While the cores of giant planets were growing via planetesimal and pebble accretion, they started to interact with the gas in the protoplanetary disc. LÄS MER

  7. 5. Metallicity determination of M dwarfs

    Författare :Sara Lindgren; Ulrike Heiter; Ansgar Reiners; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; stars: low mass - stars: abundances; fundamental parameters - technique: spectroscopic; photometric - planets and satellites: formation;

    Sammanfattning : M dwarfs constitute around 70% of all stars in the local Galaxy. Their multitude together with their long main-sequence lifetimes make them important for studies of global properties of the Galaxy such as the initial mass function or the structure and kinematics of stellar populations. LÄS MER