Peter Carl Ludwig Schwarz (Julian, O.S.: 23 May 1822, Danzig-Gdansk – 17 September 1894; Gregorian, N.S.: 4 June 1822 - 29 September 1894, St.
George's?; Buried: Tartu) (referred to mostly as Ludwig Schwarz), was a Baltic German astronomer of Imperial Russia, explorer, and professor of astronomy at the University of Dorpat honored with the Konstantin Medal of the Imperial Russian Geographical Society.
Schwarz also was a recipient of the Demidov Prize of the Academy of Sciences of St.