The initial choice of name for the asteroid was "Italia", after Italy, but this was modified to Ausonia, an ancient classical name for the Italian region.

[5][6] Vestian asteroids have a composition akin to cumulate eucrites (HED meteorites) and are thought to have originated deep within 4 Vesta's crust, possibly from the Rheasilvia crater, a large impact crater on its southern hemisphere near the South pole, formed as a result of a subcatastrophic collision.

[29] According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Ausonia measures between 87.47 and 116.044 kilometers in diameter and its surface has an albedo between 0.125 and 0.25.

[9][10][12][13][25][24] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.2082 and a diameter of 90 kilometers based on an absolute magnitude of 7.55.

[22] A lightcurve of Ausonia was obtained with the ESO 0.5-metre telescope at La Silla Observatory in 1980.