171 Ophelia

171 Ophelia is a large, dark Themistian asteroid^[5] that was discovered by French astronomer Alphonse Borrelly on 13 January 1877, and named after Ophelia in Shakespeare's Hamlet.^[6]

171 Ophelia

3D convex shape model of 171 Ophelia
Discovery
Discovered by	A. Borrelly
Discovery date	13 January 1877
Designations
MPC designation	(171) Ophelia
Pronunciation	/oʊˈfiːliə/[1]
Alternative designations	A877 AB
Minor planet category	Main belt (Themis)
Adjectives	Ophelian /ɒˈfiːliən/[2]
Orbital characteristics[3]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc	122.15 yr (44615 d)
Aphelion	3.5476 AU (530.71 Gm)
Perihelion	2.7175 AU (406.53 Gm)
Semi-major axis	3.1326 AU (468.63 Gm)
Eccentricity	0.13249
Orbital period (sidereal)	5.54 yr (2025.1 d)
Mean anomaly	11.164°
Mean motion	0° 10m 39.972s / day
Inclination	2.5461°
Longitude of ascending node	100.52°
Argument of perihelion	56.849°
Physical characteristics
Mean diameter	130.808±1.483 km[3]
Mass	(1.064 ± 0.535/0.351)×1018 kg[4]
Mean density	1.755 ± 0.883/0.579 g/cm3[4][a]
Synodic rotation period	6.66535 h (0.277723 d)
Geometric albedo	0.0615±0.004
Spectral type	C
Absolute magnitude (H)	8.31

This asteroid is a member of the Themis family of asteroids that share similar orbital elements.^[7] It probably has a primitive composition, similar to that of the carbonaceous chondrite meteorites.

A 1979 study of the Algol-like light curve produced by this asteroid concluded that it was possible to model the brightness variation by assuming a binary system with a circular orbit, a period of 13.146 hours, and an inclination of 15° to the line of sight from the Earth.^[8] Photometric observations of this asteroid at the Leura Observatory in Leura, Australia during 2006 gave a rotation period of 6.6666 ± 0.0002 hours and a brightness variation of 0.50 ± 0.02 in magnitude. This is in agreement with previous studies.^[9]

Ophelia is also the name of a moon of Uranus.

Notes

1. Assuming a diameter of 105.01 ± 3.54 km.