165 Loreley

165 Loreley is a large main-belt asteroid that was discovered by C. H. F. Peters on August 9, 1876, in Clinton, New York and named after the Lorelei, a figure in German folklore. It is orbiting the Sun at a distance of 3.125 AU and a low eccentricity of 0.08. The orbital plane is inclined at an angle of 11.2° to the plane of the ecliptic.^[2]

165 Loreley

Lightcurve-base 3D-model of Loreley on the top with an image of the asteroid on the bottom.
Discovery
Discovered by	C. H. F. Peters
Discovery date	9 August 1876
Designations
MPC designation	(165) Loreley
Pronunciation	/ˈlɔːrəlaɪ/[1]
Alternative designations	A876 PA; 1948 QS; 1959 PB; 1960 WG
Minor planet category	main belt
Orbital characteristics[2]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc	139.51 yr (50957 d)
Aphelion	3.3904 AU (507.20 Gm)
Perihelion	2.8599 AU (427.83 Gm)
Semi-major axis	3.1251 AU (467.51 Gm)
Eccentricity	0.084887
Orbital period (sidereal)	5.525 yr (2,017.9 d)
Mean anomaly	125.88°
Mean motion	0° 10m 42.24s / day
Inclination	11.224°
Longitude of ascending node	302.53°
Argument of perihelion	347.29°
Earth MOID	1.84454 AU (275.939 Gm)
Jupiter MOID	1.81383 AU (271.345 Gm)
TJupiter	3.180
Physical characteristics
Dimensions	180.083±2.064 km[2] 164.92 ± 8.14 km[3]
Mass	(1.91±0.19)×1019 kg[3]
Mean density	8.14 ± 1.46 g/cm3[3]
Synodic rotation period	7.226 h (0.3011 d)[2] 7.22667 h[4]
Geometric albedo	0.0642±0.004
Absolute magnitude (H)	7.65,[2] 7.76[5]

In the late 1990s, a network of astronomers worldwide gathered light curve data that was ultimately used to derive the spin states and shape models of 10 new asteroids, including (165) Loreley. The light curve of this asteroid varies by no more than 0.2 in magnitude, while the derived shape model shows multiple flat spots on the surface.^[4][6] The asteroid has an oblate shape with a size ratio of 1.26 ± 0.08 between the major and minor axes, as determined from the W. M. Keck Observatory.^[7]

Between 2003 and 2021, 165 Loreley has been observed to occult thirteen stars.