Orest Khvolson

Orest Danilovich Khvolson
Orest Danilovich Khvolson
Оре́ст Дани́лович Хво́льсон
	Orest Khvolson
Born	Орест Данилович Хвoльсон; 4 December 1852; Sankt-Petersburg, Russian Empire
Died	11 May 1934 (aged 81); Leningrad, Russian Empire
Resting place	Smolensky Cemetery, Saint Petersburg, Russia
Nationality	Russian Empire; Soviet Union;
Alma mater	Saint Petersburg Imperial University (magistr, 1875); Saint Petersburg Imperial University (doktor, 1880);
Known for	Einstein-Khvolson ring; Actinometer; Pyrheliometer;
Spouse(s)	Matilda Vasilyevna Khvolson, née Shondorf (died 1929)
Children	Anna Orestovna Khvolson; Vera Orestovna Khvolson;
Awards	Lomonosov Award (1892 and 1908); Order of Franz Joseph (Austria); Order of the Red Banner of Labour (1926); Hero of Labour (1927);
	Scientific career
Fields	Physics, astrophysics, meteorology
Institutions	Saint Petersburg Imperial University (1876-1929); Bestuzhev Courses (1890-1899); Karl May School; Petrischule (1876);
Thesis	"О магнитных успокоителях" (On magnetic dampers) (1880)
Academic advisors	Carl Neumann

Orest Danilovich Khvolson or Chwolson (Russian: Орест Данилович Хвольсон; November 22 (N.S. December 4), 1852 – May 11, 1934) was a Russian and later Soviet physicist and honorary member of the Soviet Academy of Sciences (1920). He is most noted for being one of the first to study the gravitational lens effect.