6102 Visby

6102 Visby, provisional designation 1993 FQ₂₅, is a stony background asteroid from the central region of the asteroid belt, approximately 5 kilometers (3.1 miles) in diameter.

6102 Visby

Discovery[1]
Discovered by	UESAC
Discovery site	La Silla Obs.
Discovery date	21 March 1993
Designations
MPC designation	(6102) Visby
Named after	Visby (Swedish town)[2]
Alternative designations	1993 FQ25 · 1990 TV11 1991 YQ2
Minor planet category	main-belt · (middle) background
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	27.87 yr (10,178 days)
Aphelion	3.0260 AU
Perihelion	2.1704 AU
Semi-major axis	2.5982 AU
Eccentricity	0.1646
Orbital period (sidereal)	4.19 yr (1,530 days)
Mean anomaly	198.43°
Mean motion	0° 14m 7.08s / day
Inclination	1.7601°
Longitude of ascending node	310.81°
Argument of perihelion	358.44°
Physical characteristics
Dimensions	4.473±0.168 km[3][4] 5.16 km (calculated)[5]
Synodic rotation period	3.28±0.01 h[6]
Geometric albedo	0.20 (assumed)[5] 0.292±0.077[3][4]
Spectral type	S[5][7]
Absolute magnitude (H)	13.7[3] · 13.72±0.21[7] · 13.76±0.18 (R)[6] · 13.8[1][5]

The asteroid was discovered on 21 March 1993, during the Uppsala-ESO Survey of Asteroids and Comets (UESAC) at the ESO's La Silla Observatory site in northern Chile.^[8] It is UESAC's lowest numbered discoveries (among more than 1,100 asteroids). It was named for the Swedish town of Visby.^[2]

Orbit and classification

Visby is a non-family asteroid from the main belt's background population. It orbits the Sun in the central main-belt at a distance of 2.2–3.0 AU once every 4 years and 2 months (1,530 days). Its orbit has an eccentricity of 0.16 and an inclination of 2° with respect to the ecliptic.^[1] A first precovery was taken at Palomar Observatory in 1989, extending the body's observation arc by 4 years prior to its official discovery observation at La Silla.^[8]

Naming

This minor planet was named after Visby, a Swedish town on the island of Gotland, known for its medieval and Hanseatic history (also see List of Gotland-related asteroids).^[2] The official naming citation was published by the Minor Planet Center on 28 September 1999 (M.P.C. 36126).^[9]

Physical characteristics

Visby has been characterized as a common S-type asteroid by PanSTARRS' photometric survey.

Rotation period

A rotational lightcurve of Visby was obtained from photometric observations at the Palomar Transient Factory in February 2013. It gave a rotation period of 3.28±0.01 hours with a brightness variation of 0.28 in magnitude (U=2+).^[6]

Diameter and albedo

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Visby measures 4.5 kilometers in diameter and its surface has an albedo of 0.29,^[3][4] while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 5.2 kilometers.^[5]