According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Sinon measures 37.86 kilometers in diameter and its surface has an albedo of 0.093, while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for a carbonaceous asteroid of 0.057 and calculates a diameter of 48.48 kilometers based on an absolute magnitude of 10.3.
