1165 Imprinetta

1165 Imprinetta, provisional designation 1930 HM, is a carbonaceous Meliboean asteroid from the outer regions of the asteroid belt, approximately 49 kilometers (30 mi) in diameter. It was discovered on 24 April 1930 by Dutch astronomer Hendrik van Gent at the Union Observatory in Johannesburg, South Africa.^[15] The asteroid was named after Imprinetta Gent, wife of the discoverer.^[2]

1165 Imprinetta

Shape model of Imprinetta from its lightcurve
Discovery[1]
Discovered by	H. van Gent
Discovery site	Johannesburg Obs. (Leiden Southern Station)
Discovery date	24 April 1930
Designations
MPC designation	(1165) Imprinetta
Pronunciation	/ˌɪmprɪˈnɛtə/
Named after	Imprinetta Gent (wife of the discoverer)[2]
Alternative designations	1930 HM · A909 TA
Minor planet category	main-belt · (outer)[3] Meliboea[4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	107.47 yr (39,253 days)
Aphelion	3.7891 AU
Perihelion	2.4589 AU
Semi-major axis	3.1240 AU
Eccentricity	0.2129
Orbital period (sidereal)	5.52 yr (2,017 days)
Mean anomaly	221.92°
Mean motion	0° 10m 42.6s / day
Inclination	12.812°
Longitude of ascending node	203.79°
Argument of perihelion	96.959°
Physical characteristics
Dimensions	47.14±15.99 km[5] 48.65 km (derived)[3] 48.82±1.9 km[6] 50.30±14.80 km[7] 53.187±0.325 km[8] 53.40±1.62 km[9] 56.44±0.87 km[10] 59.378±0.290 km[11]
Synodic rotation period	7.9374±0.0016 h[12] 8.107±0.010 h[13]
Geometric albedo	0.029±0.005[10] 0.0380±0.0055[11] 0.0392 (derived)[3] 0.04±0.02[5] 0.04±0.03[7] 0.047±0.003[9] 0.048±0.002[8] 0.0562±0.005[6]
Spectral type	C[3][14]
Absolute magnitude (H)	10.30[6][9][11] · 10.69±0.38[14] · 10.70[1][3][5][7][10]

Orbit and classification

Imprinetta is a member of the Meliboea family, a smaller asteroid family of carbonaceous outer-belt asteroids with a few hundred members, named after 137 Meliboea.^{[4][16]: 23}

This asteroid orbits the Sun in the outer main-belt at a distance of 2.5–3.8 AU once every 5 years and 6 months (2,017 days). Its orbit has an eccentricity of 0.21 and an inclination of 13° with respect to the ecliptic.^[1]

The body's observation arc begins with its first identification as A909 TA at Heidelberg Observatory in October 1909, more than 20 years prior to its official discovery observation at Johannesburg.^[15]

Physical characteristics

Imprinetta has been characterized as a carbonaceous C-type asteroid by PanSTARRS photometric survey,^[3][14] which corresponds with the overall spectral type of the Meliboea family.^[16]: 23

Rotation period

In October 2003, a rotational lightcurve of Imprinetta was obtained from photometric observations by American John Menke at his observatory in Barnesville, Maryland. Lightcurve analysis gave a well-defined rotation period of 8.107 hours with a brightness variation of 0.20 magnitude (U=3).^[13] An alternative observation gave a lightcurve with period of 7.9374 hours and an amplitude of 0.20 magnitude (U=2).^[12]

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, Imprinetta measures between 47.14 and 59.378 kilometers (29.291 and 36.896 mi) in diameter and its surface has an albedo between 0.029 and 0.0562.^{[5][6][7][8][9][10][11]}

The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0392 and a diameter of 48.65 kilometers (30.23 mi) based on an absolute magnitude of 10.7.^[3]

Naming

This minor planet was named after Imprinetta Gent, wife of the discoverer. The naming was proposed by the discoverer and by Gerrit Pels, who computed its orbit. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 108).^[2]