1925 Franklin-Adams

1925 Franklin-Adams (prov. designation: ) is a stony background asteroid from the central regions of the asteroid belt, approximately 8.9 km in diameter. It was discovered on 9 September 1934, by Dutch astronomer Hendrik van Gent at the Leiden Southern Station, annex to the Johannesburg Observatory in South Africa. The bright asteroid has a short rotation period of less than 3 hours. It was named after British amateur astronomer John Franklin Adams (1843–1912).

Orbit and classification
Franklin-Adams is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements. It orbits the Sun in the central asteroid belt at a distance of 2.1–3.0 AU once every 4 years and 1 month (1,489 days; semi-major axis of 2.55 AU). Its orbit has an eccentricity of 0.18 and an inclination of 8° with respect to the ecliptic. The body's observation arc begins with its official discovery observation at Johannesburg.

Naming
This minor planet named after British amateur astronomer John Franklin Adams (1843–1912), who created one of the earliest detailed, photographic atlases of the complete night sky (the Franklin-Adams plates or charts). He later donated his 25-cm Franklin-Adams Star Camera (Franklin-Adams photographic refractor) to the Johannesburg Observatory, which lead to the discovery of Proxima Centauri. The official was published by the Minor Planet Center on 20 December 1983 (M.P.C. 8402). Asteroid 982 Franklina, discovered by South African astronomer Harry Edwin Wood at Johannesburg was also.

Physical characteristics
Franklin-Adams is an assumed stony S-type asteroid with a very high albedo of more than 0.3 (see below).

Rotation period and poles
In January 2005, a rotational lightcurve of Franklin-Adams was obtained from photometric observations by French amateur astronomer René Roy. Lightcurve analysis gave a rotation period of 3.082 hours with a brightness amplitude of 0.23 magnitude (U=2). In March 2010, photometry at the Palomar Transient Factory in California gave a period of 2.979 with an amplitude of 0.32 magnitude (U=2). In January 2013, American astronomer Brian Warner obtained the so-far best rated lightcurve. It gave a period of 2.978 hours and an amplitude of 0.25 magnitude (U=3).

In 2016, an international study modeled a lightcurve with a concurring period of 2.978301 hours and found a spin axis of (277.0°, 57.0°) and (66.0°, 48.0°) in ecliptic coordinates (λ, β) (U=n.a.).

Diameter and albedo
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Franklin-Adams measures 8.864 kilometers in diameter and its surface has an unusually high albedo of 0.356, while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 11.30 kilometers based on an absolute magnitude of 12.1.