3905 Doppler
3905 Doppler, provisional designation, is a stony asteroid and binary system from the middle region of the asteroid belt, approximately 8 kilometers in diameter.
The asteroid was discovered on 28 August 1984, by Czech astronomer Antonín Mrkos at Kleť Observatory and named after physicist Christian Doppler.
Orbit and characterization
Doppler orbits the Sun in the central main-belt at a distance of 1.9–3.2 AU once every 4 years and 1 month. Its orbit has an eccentricity of 0.26 and an inclination of 14° with respect to the ecliptic. It has been characterized as a common S-type asteroid.A minor-planet moon orbiting Doppler every 50.8 hours was found orbiting the asteroid in 2013. This is fairly long orbital period for a moon of an asteroid of this size. The satellite's orbital period is identical to the primary's rotation period.
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Doppler measures 8.021 kilometers in diameter and its surface has an albedo of 0.228, while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 8.97 kilometers with an absolute magnitude of 12.6.