Abstract

Poster - Splinter Plasma

Tuesday, 19 September 2017, 16:05   (D+E+F MPS)

Electromagnetic star-planet-interaction at TRAPPIST-1

C. Fischer¹, J. Saur^1
1 University of Cologne, Institute of Geophysics and Meteorology

We investigate the TRAPPIST-1 system with its seven close-in terrestrial planets for possible electromagnetic star-planet-interactions. Our results show that the innermost planets, especially TRAPPIST-1b and c, are subject to sub-Alfv\'enic interaction. Both planets are therefore expected to generate Alfv\'en wings, that can couple to the star. Our model describes the stellar wind in a semi-analytic approach as a thermal wind, according to the Parker-model. Therefore we can estimate the Alfv\'en Mach number at each planet for different sets of parameters. That allows for conclusions about the type of electromagnetic interaction.