1054 Forsytia is a dark background asteroid, approximately 46 kilometers in diameter, from the outer regions of the asteroid belt. It was discovered on 20 November 1925, by astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in southwest Germany and assigned provisional designation 1925 WD. It is named after the flowering plant forsythia, and marks the beginning of a sequence of 28 thematically named asteroids by the discoverer.