Sökning: "Planets"

Visar resultat 21 - 25 av 79 avhandlingar innehållade ordet Planets.

1. 21. Studies of Gas Disks in Binary Systems

   Författare :Miguel de Val Borro; Pawel Artymowicz; William Benz; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Astronomy; Astronomi; Astronomy; astronomi;

   Sammanfattning : There are over 300 exoplanets detected through radial velocity surveys and photometric studies showing a tremendous variety of masses, compositions and orbital parameters. Understanding the way these planets formed and evolved within the circumstellar disks they were initially embedded in is a crucial issue. LÄS MER

3. 22. Circumstellar dust emission from nearby Solar-type stars

   Författare :Joachim Wiegert; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Stars: binaries - Stars: circumstellar matter - Infrared: stars - Infrared: planetary systems - Submillimeter: stars;

   Sammanfattning : Far-infrared excess above the photosphere of a star indicates the presence of a circumstellar dust disc which is a sign-post for extrasolar planets, and was first detected in the mid 1980s. Dust discs are intricately connected to planets and planetesimals, give insights in the dynamics and evolution of the system, and are also useful for future exoplanet-observations. LÄS MER

4. 23. High Resolution Transmission Spectroscopy of Exoplanets

   Författare :Ansgar Wehrhahn; Nikolai Piskunov; Ulrike Heiter; Jason Wright; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; astronomy; spectroscopy; Astronomy; Astronomi;

   Sammanfattning : A large number of exoplanets has been observed in the last three decades, but still for most of them we know comparatively little about the atmospheres of these distant planets. This is of particular interest as there exist types of planets that don't have an analogy in our own solar system, like hot Jupiters or super Earths. LÄS MER

5. 24. The induced magnetospheres and magnetotails of Mars and Venus

   Författare :Aikaterini Stergiopoulou; David Andrews; Niklas Edberg; Lasse Clausen; Uppsala universitet; []
   Nyckelord :Mars; Venus; Ionosphere; Induced Magnetosphere; Induced Magnetotail;

   Sammanfattning : In this work we focus on several aspects of the ionospheres, induced magnetospheres, and magnetotails of the unmagnetized planets Mars and Venus. The solar wind interaction with unmagnetized planets differs from the magnetized planets: they are more directly exposed to the solar wind, and consequently can respond faster and more dynamically to solar wind variations, necessitating careful analysis of the driving conditions upstream simultaneously with plasma measurements in the system. LÄS MER

7. 25. High-Contrast Investigation of the ε Ind system

   Författare :Gayathri Viswanath; Markus Janson; Alexis Brandeker; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; astronomi;

   Sammanfattning : This licentiate thesis provides a broad introduction into the methodology of detecting and characterising exoplanets, with the main focus on the method of high-contrast imaging (HCI). Developments in theoretical knowledge as well as instrumentation have, in the past decade, pushed the boundaries of what HCI can achieve, both in terms of detection sensitivity and constraining planet properties. LÄS MER