178 Belisana

178 Belisana is a stony background asteroid from the inner regions of the asteroid belt, approximately 38 kilometers (24 miles) in diameter. It was discovered on 6 November 1877, by Austrian astronomer Johann Palisa at the Austrian Naval Observatory in today's Croatia.^[1] The S-type asteroid has a rotation period of 12.32 hours and a rather spherical shape.^[6] It was named after the Celtic goddess Belisama (Belisana).^[2]

178 Belisana

Lightcurve-based 3D-model of Belisana
Discovery[1]
Discovered by	J. Palisa
Discovery site	Austrian Naval Obs.
Discovery date	6 November 1877
Designations
MPC designation	(178) Belisana
Pronunciation	/bɛˈlɪsənə/
Named after	Bēlēsama[2] (Celtic mythology)
Alternative designations	A877 VB; 1899 LE; 1904 UA; 1935 UA1
Minor planet category	main-belt[1][3] · (inner) background[4][5]
Orbital characteristics[3]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc	132.36 yr (48,345 d)
Aphelion	2.5667 AU
Perihelion	2.3536 AU
Semi-major axis	2.4601 AU
Eccentricity	0.0433
Orbital period (sidereal)	3.86 yr (1,409 d)
Mean anomaly	272.93°
Mean motion	0° 15m 19.44s / day
Inclination	1.8950°
Longitude of ascending node	51.109°
Argument of perihelion	212.67°
Physical characteristics
Mean diameter	35.50 km (derived)[6] 35.81±0.9 km[7] 38.26±1.12 km[8] 42.09±11.05 km[9]
Synodic rotation period	12.31±0.07 h[10] 12.32±0.05 h[10] 12.321±0.003 h[11] 12.323±0.002 h[12] 24.6510±0.0003 h[13]
Geometric albedo	0.2026 (derived)[6] 0.214±0.016[8] 0.22±0.09[9] 0.2438±0.013[7]
Spectral type	Tholen = S[3] SMASS = S[3] · S[6] B–V = 0.904[3] U–B = 0.486[3]
Absolute magnitude (H)	9.38[7][8] 9.4[3] 9.52[9] 9.6[6][11][14] 9.66±0.79[15]

Orbit and classification

Belisana is a non-family asteroid from the main belt's background population.^[4][5] It orbits the Sun in the inner main-belt at a distance of 2.4–2.6 AU once every 3 years and 10 months (1,409 days; semi-major axis of 2.46 AU). Its orbit has an eccentricity of 0.04 and an inclination of 2° with respect to the ecliptic.^[3]

Physical characteristics

Belisana has been characterized as a common, stony S-type asteroid in both the Tholen and SMASS classification.^[3]

Rotation period

Photometric observations of this asteroid from multiple observatories during 2007 gave a light curve with a period of 12.321 ± 0.002 hours and a brightness variation of 0.10 ± 0.03 in magnitude. This is in agreement with a study performed in 1992. However, it is possible that the light curve may have a period of 24.6510 ± 0.0003 hours; it will require further study to exclude this solution.^[13]

Diameter and albedo

According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Belisana measures between 35.81 and 42.09 kilometers in diameter and its surface has an albedo between 0.214 and 0.2438.^[7][8][9]

The Collaborative Asteroid Lightcurve Link derives an albedo of 0.2026 and a diameter of 35.50 kilometers based on an absolute magnitude of 9.6.^[6]

Naming

This minor planet was named after the goddess Belisama (or Belisana) from Celtic mythology, meaning "queen of heaven", the most warlike goddess among British Celts, and equivalent to the goddesses Athene or Minerva. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 22).^[2]