1076 Viola

1076 Viola /ˈvaɪ.ələ/,^[16] provisional designation 1926 TE, is a Nysian asteroid from the inner regions of the asteroid belt, approximately 22 kilometers in diameter. It was discovered on 5 October 1926, by German astronomer Karl Reinmuth at the Heidelberg Observatory in southwest Germany.^[17] The asteroid was named after the flowering plant Viola.^[3]

1076 Viola

Discovery[1]
Discovered by	K. Reinmuth
Discovery site	Heidelberg Obs.
Discovery date	5 October 1926
Designations
MPC designation	(1076) Viola
Pronunciation	/ˈvaɪ.ələ/[2]
Named after	Viola (flowering plant)[3]
Alternative designations	1926 TE
Minor planet category	main-belt · (inner) Nysa[4] · background[5]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	90.48 yr (33,048 days)
Aphelion	2.8323 AU
Perihelion	2.1164 AU
Semi-major axis	2.4744 AU
Eccentricity	0.1447
Orbital period (sidereal)	3.89 yr (1,422 days)
Mean anomaly	70.608°
Mean motion	0° 15m 11.52s / day
Inclination	3.3195°
Longitude of ascending node	143.71°
Argument of perihelion	304.08°
Physical characteristics
Dimensions	21.412±7.130 km[6] 21.43±6.81 km[7] 22.0±2.2 km[8] 22.273±0.069 km[9] 22.298±0.117 km[10] 22.63±2.7 km[11] 23.57±7.70 km[12] 24±2 km[13] 26.39±0.61 km[14]
Synodic rotation period	7.336 h[15]
Geometric albedo	0.032±0.002[14] 0.0375±0.0535[6] 0.04±0.01[8][13] 0.04±0.02[12] 0.04±0.05[7] 0.041±0.004[10] 0.0415±0.012[11] 0.0428±0.0046[9]
Spectral type	Tholen = F[1] SMASS = C[1][4] B–V = 0.629[1] U–B = 0.250[1]
Absolute magnitude (H)	12.21[12] · 12.30[1][4][6][7][8][9][11][13][14]

Orbit and classification

Viola is a non-family asteroid of the main belt's background population when applying the Hierarchical Clustering Method to its proper orbital elements.^[5] The asteroid has also been classified as a member of the Nysa family (405),^[4] the largest asteroid family of the main belt, consisting of stony and carbonaceous subfamilies. The family, named after 44 Nysa, is located near the Kirkwood gap (3:1 orbital resonance with Jupiter), a depleted zone that separates the central main belt.

Viola orbits the Sun in the inner asteroid belt at a distance of 2.1–2.8 AU once every 3 years and 11 months (1,422 days; semi-major axis of 2.47 AU). Its orbit has an eccentricity of 0.14 and an inclination of 3° with respect to the ecliptic.^[1] The body's observation arc begins at Heidelberg in January 1951, or more than 24 years after its official discovery observation.^[17]

Physical characteristics

In the Tholen classification, Viola is a rare F-type asteroid, while in the SMASS taxonomy, it is classified as a common, carbonaceous C-type.^[1][4]

Rotation period

In the 1980s, a rotational lightcurve of Viola was obtained from photometric observations by American astronomer Richard Binzel. Lightcurve analysis gave a well-defined rotation period of 7.336 hours with a brightness amplitude of 0.12 magnitude (U=3).^[15] A tentative period of 14.4 hours was measured by French amateur astronomer René Roy in January 2009, but later retracted from the LCDB (U=n.a.).^[4][18]

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, Viola measures between 21.412 and 26.39 kilometers in diameter and its surface has an albedo between 0.032 and 0.0428.^{[6][7][8][9][10][11][12][13][14]}

The Collaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is, an albedo of 0.0415 and a diameter of 22.63 kilometers based on an absolute magnitude of 12.30.^[4][11]

Naming

This minor planet was named after Viola, a genus of flowering plants within the violet family. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 102).^[3]

Reinmuth's flowers

Due to his many discoveries, Karl Reinmuth submitted a large list of 66 newly named asteroids in the early 1930s. The list covered his discoveries with numbers between (1009) and (1200). This list also contained a sequence of 28 asteroids, starting with 1054 Forsytia, that were all named after plants, in particular flowering plants (also see list of minor planets named after animals and plants).^[19]