682 Hagar (prov. designation: or ) is an Eunomia asteroid from the central regions of the asteroid belt. It was discovered on 17 June 1909, by German astronomer August Kopff at the Heidelberg-Königstuhl State Observatory. The presumed S-type asteroid has a short rotation period of 4.9 hours and measures approximately in diameter. Possibly inspired by the asteroid's provisional designation "1909 HA", it was named for the biblical woman Hagar. Orbit and classification When applying the hierarchical clustering method to its proper orbital elements, Hagar is a core member of the Eunomia family (), a prominent family of stony S-type asteroids and the largest one in the intermediate main belt with more than 5,000 known members. It orbits the Sun in the central main-belt at a distance of 2.2–3.1 AU once every 4 years and 4 months (1,579 days; semi-major axis of 2.65 AU). Its orbit has an eccentricity of 0.17 and an inclination of 12° with respect to the ecliptic. The body's observation arc begins at Vienna Observatory on 28 June 1909, just eleven nights after prior to its official discovery observation by August Kopff at Heidelberg. Naming This minor planet was named after the biblical woman Hagar from the Book of Genesis. She was an Ancient Egyptian servant of Sarah and the mother of Abraham's firstborn, Ishmael. The asteroid's name may have been inspired by the two letters of its provisional designation, "1909 HA". It is also speculated that the name comes from a list created in 1913 by the Astronomisches Rechen-Institut (ARI) containing suggestions of female names from history and mythology for the naming of minor planets (AN 196, 137). At the time, the naming process was not well developed and the ARI feared inconsistencies and potential confusion. The list was sent to several German astronomers, including Kopff, with the invitation to name all of their made discoveries up to number 700. Physical characteristics Based on the overall spectral type of the Eunomia family, Hagar is possibly a common, stony S-type asteroid. However, observations by Pilcher (see below) found a V–R color index of , which rather suggest a low albedo of a carbonaceous C-type asteroid. Rotation period In August 2013, a rotational lightcurve of Hagar was obtained from nine nights of photometric observations by Frederick Pilcher at the Organ Mesa Observatory in Arizona. Analysis gave a well-defined, classically shaped bimodal lightcurve with a rotation period of ()