Ioannis S. Paraskevopoulos

John Stefanos Paraskevopoulos (Greek: Ιωάννης Στέφανος Παρασκευόπουλος; June 20, 1889 – March 15, 1951) also known as John Paras, was a Greek and South African astronomer. He spent most of his career in the Boyden Observatory, for the establishment of which he played a crucial role.

He was born in Piraeus, Kingdom of Greece and graduated from the University of Athens, where he obtained his PhD in physics in 1910, under the supervision of Timoleon A. Argyropoulos. His thesis was entitled "Variability in absorption spectra". After his graduation he spent several years as laboratory assistant in Physics and Chemistry at the University of Athens, with King George II attending laboratory courses under him at that time.

His scientific career was interrupted by nine years of military service in the Greek army during the Balkan Wars and World War I. He ended his military career with the rank of First Lieutenant and received multiple war medals including thirteen bars for battles in which he had fought. During part of his military service he was an instructor in navigation at the National Observatory of Athens.

He co-discovered a couple of comets, including C/1941 B2 (de Kock–Paraskevopoulos), which became visible with naked eye. The crater Paraskevopoulos on the Moon and the asteroid 5298 Paraskevopoulos are named after him.