Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 195-199).

Kiel, Univ., Diss., 2000. / Computerdatei im Fernzugriff.

Inaug.-Diss.--Iena. / Vita.

Thèse--Faculté des sciences de Paris, 1865.

Kiel, Universiẗat, Diss., 2000.

Heidelberg, University, Diss., 2001.

This thesis describes observations of the flne structure in Jovian decametric radiation made at Grahamstown during the 1967-68 apparition. It was found that pulses with duration less than 0.5 milliseconds were common during fine structure storms. The restrictions placed on the source for different theories of origin of the short pulses are discussed. The variation of the probability of occurrence from year to year is analysed on the assumption that the radiation is found in directions fixed with respect to the planet's magnetic field. It is concluded that there is a factor other than the declination of Earth and the Io effect which controls the probability of occurrence. A detailed analysis suggests a beam width of 3° in latitude at Jupiter but further work is necessary to check this.

The silicate "magma trigger" model of volcanism on Io has been evaluated numerically with finite element methods by considering the one-dimensional heat transfer between hot silicate magma and initially cold sulfur. It is found that for the probable range of initial magma temperatures and sulfur temperatures, the contact between silicate magma and a sulfur crust will be 700 (+OR-) 100 K, or approximately the vapor point of elemental sulfur. A silicate magma sill or laccolith on the order of 10 m thick will yield energetic vapor for a period of several weeks to several months depending on the vapor temperature and the amount of convective cooling of the silicate magma that occurs at the silicate-sulfur interface. This model may account for the origin of plumes and possible sulfur flows, as well as for their observed temperatures ((TURN) 600-700K) and lifetimes (several days to a few months). If the conducted heat flow is similar in high and low latitudes, then the low latitude occurrence of plumes may be explained as a result of lower temperatures at higher latitudes. Because the contact temperature of sulfur and silicate magma depends on the pre-existing sulfur temperature, a system in which sulfur vapor temperature is just reached at the equator would not generate sulfur vapor under lower initial sulfur temperatures existing at high latitudes. If the heat flow is higher in high latitudes, then the sulfur crust must be thinner than it is in low latitudes for the model to work as described above. Most of the heat flow from Io may be moved by convection from the interior to the surface, not by conduction. Heat flow may be modulated by the efficient transfer of silicate melts from 40 to 300 km depth, and emplaced as laccoliths at the sulfur-silicate crustal interfaces at a depth of 5-10 km. Sulfur flows, plumes, calderas and other areas of massive radiant heat dissipation continue the convective cycle to the surface. The temperature at the base of the sulfur crust may be less than the melting point of sulfur, and the silicate magma temperature can be as low as 1200 K. Low silicate magma temperatures will occur if the crust of Io is as differentiated as terrestrial rhyolites and trachytes. High alkalies in the Io plasma torus suggest the possibility that the Ionian crust is a highly differentiated silicate.

The field of exoplanets have been rapidly growing, confirming over three thousand planets of which most have been discovered with the Transit method. Now focus lies on the characterization of exoplanets atmospheres. The searches are concentrated on finding planets that are Earth-like and in the habitable zone in order to detect biosignatures, the sign of life. This project examines Earth as an exoplanet. The goal of the project is to answer if it is possible to see Earth's atmosphere when transiting the Sun as seen from Jupiter. In January 5 2014 Jupiter was observed during the Earth-transit on the Sun as seen from Jupiter. Spectra were taken with the infrared spectrograph CRIRES, located at Cerro Paranal in Chile, during the last part and after the transit. The spectra were reduced and a combined 2d spectra were obtained. A detailed analysis process was performed and the spectra during transit was divided by the spectra after transit, giving a residual signal. The residual signal was compared to the telluric spectrum in order to determine if they correlated. A correlation of the lines might indicate that Earth’s atmosphere is detected in the dataset. The residual signal correlates with the telluric absorption lines, but the conclusion is that the signal is probably due to incomplete removal of telluric lines. / Exoplaneter har varit ett snabbt växande område, nu med över tretusen bekräftade planeter. Flest exoplaneter har blivit upptäckta med Transitmetoden och sedan upptäckten av en exoplanets atmosfär gjordes ligger mycket fokus på karaktärisering av dessa atmosfärer. Sökandet efter en planet som liknar Jorden pågår och att detektera ämnen i atmosfären som är kopplade till liv är ett av de största målen. I detta projekt undersöks Jorden som en exoplanet. Målet är att besvara frågan om det är möjligt att se Jorden göra en transit framför solen från Jupiter sett. Den 5 januari 2014 observerades Jupiter då Jorden gjorde en transit. Spektra togs med den infraröda spektrografen CRIRES, belägen i Cerro Paranal i Chile, under den sista delen av transiten och timmarna efter. Alla spektra reducerades och ett kombinerat 2d spektra erhölls. Dessa spektra genomgick en detaljerad analysprocess och spektra taget under transiten divideras med spektra taget efter transiten och en signal erhölls. Signalen jämfördes med de telluriska absorptionslinjerna för att hitta en korrelation, vilket skulle kunna betyda att signalen från Jordens atmosfär under transiten är synlig. Signalen och de telluriska linjerna korrelerade, men slutsatsen var att denna signal förmodligen är en kvarvarande signal från de ofullständigt avlägsnade telluriska linjerna.

Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 96-100).