1617 Alschmitt

1617 Alschmitt, provisional designation 1952 FB, is an assumed carbonaceous asteroid from in the outer parts of the main belt, approximately 30 kilometers in diameter. It was discovered on 20 March 1952, by French astronomer Louis Boyer at Algiers Observatory in Algeria, Northern Africa, and named after French astronomer Alfred Schmitt.^[2][9]

1617 Alschmitt

Discovery[1]
Discovered by	L. Boyer
Discovery site	Algiers Obs.
Discovery date	20 March 1952
Designations
MPC designation	(1617) Alschmitt
Named after	Alfred Schmitt (astronomer)[2]
Alternative designations	1952 FB · 1929 CC1 1935 ER · 1941 HH 1947 LS · 1952 DK2 1975 AJ · A906 DC
Minor planet category	main-belt · (outer)[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	111.18 yr (40,607 days)
Aphelion	3.6085 AU
Perihelion	2.7913 AU
Semi-major axis	3.1999 AU
Eccentricity	0.1277
Orbital period (sidereal)	5.72 yr (2,091 days)
Mean anomaly	167.85°
Mean motion	0° 10m 19.92s / day
Inclination	13.265°
Longitude of ascending node	154.96°
Argument of perihelion	24.216°
Physical characteristics
Dimensions	21.12±2.86 km[4] 21.283±0.267 km[5][6] 36.78 km (calculated)[3]
Synodic rotation period	7.0602±0.0033 h[7] 7.0613±0.0007 h[8] 7.062±0.002 h[8]
Geometric albedo	0.057 (assumed)[3] 0.190±0.046[4] 0.270±0.020[5][6]
Spectral type	C[3]
Absolute magnitude (H)	10.4[5] · 10.80[4] · 10.807±0.002 (R)[7] · 10.9[1][3]

Orbit and classification

This asteroid orbits the Sun in the outer main-belt at a distance of 2.8–3.6 AU once every 5 years and 9 months (2,091 days). Its orbit has an eccentricity of 0.13 and an inclination of 13° with respect to the ecliptic.^[1] Alschmitt was first identified as A906 DC at Heidelberg in 1906, extending the body's observation arc by 46 years prior to its official discovery observation.^[9]

Physical characteristics

Alschmitt is a presumed carbonaceous C-type asteroid.^[3]

Lightcurves

Two rotational lightcurve of Alschmitt obtained in 2003 and 2004, by René Roy and Laurent Bernasconi, gave a well-defined rotation period of 7.0613 and 7.062 hours with a brightness variation of 0.39 and 0.52 in magnitude, respectively (U=3/3).^[7] In October 2010, the Palomar Transient Factory derived a period of 7.0602 hours with an amplitude 0.49 magnitude (U=2).^[7]

Diameter and albedo

According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Alschmitt measures 21.12 and 21.28 kilometers in diameter, and its surface has an albedo of 0.190 and 0.270, respectively.^[4][5][6] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a diameter of 36.78 kilometers using an absolute magnitude of 10.9.^[3]

Naming

Boyer named this minor planet for his colleague Alfred Schmitt (1907–1973), astronomer at Algiers, Strasbourg and Quito observatories, who, 20 years earlier, had named the asteroid 1215 Boyer in his honor.^[2] The official naming citation was published by the Minor Planet Center on 1 August 1978 (M.P.C. 4418).^[10]