It was discovered on 5 May 1935, by Dutch astronomer Hendrik van Gent at the Leiden Southern Station, annex to the Johannesburg Observatory in South Africa.

[1] Hertzsprung orbits the Sun in the central main-belt at a distance of 2.0–3.6 AU once every 4 years and 8 months (1,707 days).

[14] According to the space-based surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Hertzsprung measures between 30.95 and 41.97 kilometers in diameter and its surface has an albedo between 0.03 and 0.059.

[4][5][6][7][8][9][10] The Collaborative Asteroid Lightcurve Link agrees with the results obtained by IRAS, that is an albedo of 0.048 and a diameter of 38.7 kilometers with an absolute magnitude of 10.97.

[9] In August 1987, a rotational lightcurve of Hertzsprung was obtained from photometric observations made with the ESO 1-metre telescope at La Silla Observatory in Chile.