2490 Bussolini

2490 Bussolini (prov. designation: 1976 AG) is an Eunomia asteroid from the central region of the asteroid belt, approximately 12 kilometers (7.5 miles) in diameter. It was discovered on 3 January 1976, by staff members of the Félix Aguilar Observatory at El Leoncito Complex in Argentina.^[7] The asteroid was named after Argentine Jesuit physicist Juan Bussolini.^[2]

2490 Bussolini

Shape model of Bussolini from its lightcurve
Discovery[1]
Discovered by	Felix Aguilar Obs.
Discovery site	El Leoncito Complex
Discovery date	3 January 1976
Designations
MPC designation	(2490) Bussolini
Named after	Juan Bussolini (Argentine Jesuit physicist)[2]
Alternative designations	1976 AG · 1962 WN2 1977 KK · 1978 NT3 1978 QH
Minor planet category	main-belt · Eunomia[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	67.13 yr (24,519 days)
Aphelion	2.9567 AU
Perihelion	2.2617 AU
Semi-major axis	2.6092 AU
Eccentricity	0.1332
Orbital period (sidereal)	4.21 yr (1,539 days)
Mean anomaly	9.8678°
Mean motion	0° 14m 2.04s / day
Inclination	12.964°
Longitude of ascending node	212.60°
Argument of perihelion	210.46°
Physical characteristics
Mean diameter	11.725±0.081 km[4] 12.707±0.170 km[5] 12.09 km (calculated)[3]
Synodic rotation period	24 h[6]
Geometric albedo	0.1918±0.0207[5] 0.21 (assumed)[3] 0.223±0.043[4]
Spectral type	P[5] · S[3]
Absolute magnitude (H)	11.9[1][3][5]

Classification and orbit

Bussolini is a member of the Eunomia family, a large group of typically stony asteroids and the most prominent family in the intermediate main-belt. It orbits the Sun at a distance of 2.3–3.0 AU once every 4 years and 3 months (1,539 days). Its orbit has an eccentricity of 0.13 and an inclination of 13° with respect to the ecliptic.^[1] A first precovery was taken at Palomar Observatory in 1949, extending the body's observation arc by 27 years prior to its official discovery observation at El Leoncito.^[7]

Naming

This minor planet was named in memory Argentine Jesuit and solar physicist Juan Antonio Bussolini (1905–1966), director of the Observatorio de Fisica Cosmica de San Miguel and a noted supporter of the Felix Aguilar Observatory.^[2] The approved naming citation was published by the Minor Planet Centeron 15 May 1984 (M.P.C. 8800).^[8]

Physical characteristics

Eunomians are typically S-type asteroid.^[3] Bussolini has also been characterized as a P-type asteroid by the Wide-field Infrared Survey Explorer (WISE).^[5]

Lightcurve

In October 2008, a rotational lightcurve of Bussolini was obtained from photometric observations by French amateur astronomer Pierre Antonini. Analysis of the fragmentary lightcurve gave a somewhat longer than average rotation period of 24 hours with a brightness variation of 0.1 magnitude (U=1).^[6] As of 2017, no improved period has been obtained.^[3]

Diameter and albedo

According to the surveys carried out by NASA's WISE observatory with its subsequent NEOWISE mission, Bussolini measures 11.725 and 12.707 kilometers in diameter and its surface has an albedo of 0.223 and 0.1918, respectively.^[4][5] The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.21 – derived from 15 Eunomia, the family's largest member and namesake – and calculates a diameter of 12.09 kilometers with an absolute magnitude of 11.9.^[3]