1) Christiaan huygens 2) Christian huygens 3) Dutch surname 4) Impact crater on Mars 5) Physicist 
[Martian Crater] This category includes people from localities that were part of East Sussex before 1974. ...[spacecraft] Huygens was an atmospheric entry probe that landed successfully on Saturn`s moon Titan in 2005. Built and operated by the European Space Agency (ESA), it was part of the Cassini–Huygens mission and became the first spacecraft ever to land on Titan. The probe was named after the Dutch 17th-century astronomer Christiaan Huygens...
Type: Term Pronunciation: hoy′genz Definitions: 1. Christian, Dutch physicist, 1629-1695. See: Huygens ocular, Huygens principle
[n] - Dutch physicist who first formulated the wave theory of light (1629-1695)
1629–95, Dutch mathematician, physicist, and astronomer.