He discovered the periodic comet 53P/Van Biesbroeck, as well as two non-periodic comets: C/1925 W1 (Van Biesbroeck 1) and C/1935 Q1 (Van Biesbroeck 2).
Hien hat de periodesche Koméit 53P/Van Biesbroeck entdeckt, genee sou wéi déi netperiodesch Koméiten C/1925 W1 (Van Biesbroeck 1) an C/1935 Q1 (Van Biesbroeck 2).