Prof. Dr. phil. nat. Michael Soffel is the director of the Lohrmann Observatory of the Technical University Dresden. He is an internationally known expert in relativistic celestial mechanics, relativistic astronomy and geodesy and experimental gravity research. He is the author of the book "Relativity in Astrometry, Celestial Mechanics and Geodesy", Springer-Verlag (1989).
Dr. Ing. Ralf Langhans is working in the field of planetary geodesy and has been teaching astronomical geodesy and various courses in engineering geodesy.