Previous to his appointment at AUS, Nidhal Guessoum spent two years as a post-doctoral researcher at NASA's Goddard Space Flight Center then taught in Algeria and Kuwait. His area of expertise is cosmic gamma-ray sources (the galactic center, accretion disks, bursts, etc.), but he has also written many articles and several books on issues related to science, education and Islam, such as 'Islamic Astronomy' (the crescent observation problem, the Islamic calendar, etc.).