Complex sentence: He studied physics at the University of Szeged, Hungary, and received his Ph.D. from the University of Heidelberg in 2004, and was on astronomer at the Space Telescope Science Institute.
Split into simpler sentences: He studied physics at the University of Szeged, Hungary, and received his Ph.D. from the University of Heidelberg in 2004. He was on astronomer at the Space Telescope Science Institute.