* Astronomy

Members Login
Post Info TOPIC: Evaporating extrasolar planets


L

Posts: 131433
Date:
Evaporating extrasolar planets
Permalink  
 


Title: Evaporation of extrasolar planets
Authors: A. Lecavelier des Etangs

This article presents a review on the observations and theoretical modelling of the evaporation of extrasolar planets. The observations and the resulting constraints on the upper atmosphere (thermosphere and exosphere) of the "hot-Jupiters". are described. The early observations of the first discovered transiting extrasolar planet, HD209458b, allowed the discovery that this planet has an extended atmosphere of escaping hydrogen. Subsequent observations showed the presence of oxygen and carbon at very high altitude. These observations give unique constraints on the escape rate and mechanism in the atmosphere of hot-Jupiters. The most recent Lyman-alpha HST observations of HD189733b and MgII observations of Wasp-12b allow for the first time comparison of the evaporation from different planets in different environments. Models to quantify the escape rate from the measured occultation depths, and an energy diagram to describe the evaporation state of hot-Jupiters are presented. Using this diagram, it is shown that few already known planets like GJ876d or CoRot-7b could be remnants of formerly giant planets.

Read more (561kb, PDF)



__________________
Page 1 of 1  sorted by
 
Quick Reply

Please log in to post quick replies.



Create your own FREE Forum
Report Abuse
Powered by ActiveBoard