2440 Educatio

2440 Educatio /ɛdjuːˈkeɪʃioʊ/ is a Florian asteroid from the inner regions of the asteroid belt, approximately 6.6 kilometers (4.1 miles) in diameter. The possibly elongated S-type asteroid has an exceptionally long rotation period of 1561 hours and is one of the slowest rotators known to exist.^[5] It was discovered on 7 November 1978, by American astronomers Eleanor Helin and Schelte Bus at the Palomar Observatory in California,^[1] and later named "Educatio", the Latin word for Education.^[2]

2440 Educatio

Discovery[1]
Discovered by	E. F. Helin S. J. Bus
Discovery site	Palomar Obs.
Discovery date	7 November 1978
Designations
MPC designation	(2440) Educatio
Pronunciation	/ɛdjuːˈkeɪʃioʊ/
Named after	Education (ēducātio)[2]
Alternative designations	1978 VQ4 · 1928 QH 1954 JK · 1968 US1 1977 JG
Minor planet category	main-belt[1][3] · (inner) Flora[4][5]
Orbital characteristics[3]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc	89.43 yr (32,665 d)
Aphelion	2.5763 AU
Perihelion	1.8554 AU
Semi-major axis	2.2158 AU
Eccentricity	0.1627
Orbital period (sidereal)	3.30 yr (1,205 d)
Mean anomaly	77.238°
Mean motion	0° 17m 55.68s / day
Inclination	4.1060°
Longitude of ascending node	227.20°
Argument of perihelion	77.865°
Physical characteristics
Mean diameter	6.586±0.128 km[6]
Synodic rotation period	1561 h[5]
Geometric albedo	0.247±0.039[6]
Spectral type	S (SMASS-II)[4]
Absolute magnitude (H)	13.1[1][3]

Orbit and classification

Educatio member of the Flora family (402),^[4] a giant asteroid family and the largest family of stony asteroids in the main-belt.^[7] It orbits the Sun in the inner main-belt at a distance of 1.9–2.6 AU once every 3 years and 4 months (1,205 days; semi-major axis of 2.22 AU). Its orbit has an eccentricity of 0.16 and an inclination of 4° with respect to the ecliptic.^[3]

The asteroid was first observed as 1928 QH at the Simeiz Observatory in August 1928. The body's observation arc begins with its observation as 1954 JK at the Goethe Link Observatory in May 1954, more than 24 years prior to its official discovery observation at Palomar.^[1]

Naming

This minor planet was named "Educatio", the Latin word for Education, one of the most important human endeavors, which is foremost to the industrialization of space.^[1] The official naming citation was published by the Minor Planet Center on 28 January 1983 (M.P.C. 7618).^[8]

Physical characteristics

In the SMASS classification, Educatio is a stony S-type asteroid,^[5] which agrees with the overall spectral type for members of the Flora family.^[7]: 23

Rotation period

A rotational lightcurve of Educatio, obtained from photometric observations, gave a rotation period of 1561 hours with a high brightness amplitude of 0.80 magnitude (U=2), indicative of a non-spherical shape.^[5] It belongs to the small group of slow rotators with a period above 1000 hours.

Diameter and albedo

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Educatio measures 6.59 kilometers in diameter and its surface has an albedo of 0.247,^[6] while the Collaborative Asteroid Lightcurve Link an albedo of 0.24 – derived from 8 Flora, the parent body of the Flora family – and calculates a diameter of 6.51 kilometers based on an absolute magnitude of 13.1.^[5]