Archives

NASA Astrobiology Institute: September 2008


Date/Time: Monday, September 29, 2008 11:00AM Pacific
Speaker: Norm Sleep, Stanford University

Abstract: Silicate super-earths are rocky planets with masses up to ~10 that of the Earth. They are of astrobiological interest because they are relatively easy to detect around other stars. Tectonics enhances habitability on the Earth by exhuming biologically important elements. Plate tectonics are too poorly understood on the Earth to tell whether this process should occur on larger planets. Still the Gauss' law relationship that surface heat flow scales with surface gravity provides some insight and yields that the geotherm expressed in terms of pressure is to the first order invariant to planetary size.