since 1995 lesch has been a professor of theoretical astrophysics at the institute for astronomy and astrophysics at the lmu munich. additionally, he teaches natural philosophy at the university for philosophy in munich. his main areas of research are cosmic plasma physics, black holes, and neutron stars. he is the expert on astrophysics in the deutsche forschungsgemeinschaft (dfg) (german research society) and a member of the astronomische gesellschaft (astronomical society). he is also a textbook author.