Complex sentence: James Lauer Green is an American physicist his Ph.D. in Space Physics from the University of Iowa in 1979 and began working in the Magnetospheric Physics Branch at NASA's Marshall Space Flight Center (MSFC) in 1980.
Split into simpler sentences: James Lauer Green is an American physicist who received his Ph.D. in Space Physics from the University of Iowa in 1979 and who worked at NASA since then. He began working in the Magnetospheric Physics Branch at NASA's Marshall Space Flight Center in 1980.