Magnetic Fields and Habitability in Super Earths

Pablo A. Cuartas-Restrepo
Título conseguido: 
Doctor en Física
Ciencias Planetarias, Astrofísica
Instituto de Física, Universidad de Antioquia
Fecha de Grado: 
Thursday, December 5, 2013 - 15:30
Jorge I. Zuluaga
During the past 20 years the search and discovery of exoplanets come turns in one of the most ex- citing field in research for astronomers. A lot of these new worlds are Earth-like planets, rocky, iron and water rich objetcs. Some of them are inside the Habitable Zone of their host stars. This is our first step to find a place that looks like ours. Many conditions are required before a planet can be consider suitable to engender and sustain life during billions of years as our planet do. There are a lot of criteria to define a habitable planet, the most of them related only with the surficial temperature and the presence of liquid water on the surface. To sustain the environment for life, the planet needs an atmosphere and additionally, it must have a magnetic field to protect the atmosphere. The rotation and thermal evolution of a planet plays a main role in the planetary magnetic field evo- lution. The rotation period determines properties like the regime of the planetary dynamo and its intensity. This is crucial for a planet to keep its reservoir of volatile material like water, protected against the erosive action of the stellar wind and cosmic rays. Planets orbiting dwarf stars are tidally afected by their host, this detemines the final rotation period (resonance) or the tidal locking of the planet, especially during the very first Myr. At the same time this first period of the planet history is the most afected by the magnetic activity of the host star. We calculate the rotation and tidal evolution of planets and combine this with a thermal evolution model to know how this very first stages of the planetary evolution finish with an stable and protective planetary magnetic field or with an unprotected planet.

Zuluaga, Jorge I.; Cuartas-Restrepo Pablo A. 2012. The role of rotation in the evolution of dynamo-generated magnetic fields in Super Earths. Icarus, Volume 217, Issue 1, p. 88- 102.
Zuluaga, Jorge I.; Bustamante, Sebastian; Cuartas-Restrepo, Pablo A.; Hoyos, Jaime H. 2013. The Influence of Thermal Evolution in the Magnetic Protection of Terrestrial Planets. The Astrophysical Journal, Volume 770, Issue 1, article id. 23, 23 pp.
Zuluaga,JorgeI.;Salazar,JuanF.;Cuartas-Restrepo,PabloA.;PovedaG.Towardsthedefini- tion of an Inhabitated Habitable Zone: including the key role of life at assessing planetary habitability. In preparation.