201 Penelope

201 Penelope is a large main belt asteroid that was discovered by Austrian astronomer Johann Palisa on August 7, 1879, in Pola. The asteroid is named after Penelope, the wife of Odysseus in Homer's The Odyssey. It is orbiting the Sun at a distance of 2.68 AU with an eccentricity (ovalness) of 0.18 and a period of 4.381 years. The orbital plane is tilted at an angle of 5.8° to the plane of the ecliptic.^[2]

201 Penelope

A three-dimensional model of 201 Penelope based on its light curve.
Discovery
Discovered by	Johann Palisa
Discovery date	7 August 1879
Designations
MPC designation	(201) Penelope
Pronunciation	/pɪˈnɛləpiː/[1]
Named after	Penelópē
Alternative designations	A879 PA; 1869 GA
Minor planet category	Main belt
Adjectives	Penelopean /pɪˈnɛloʊˈpiːən/[1]
Orbital characteristics[2]
Epoch 21 January 2022 (JD 2457600.5)
Uncertainty parameter 0
Observation arc	142.58 yr (52,077 d)[3]
Aphelion	3.160 AU (472.710 Gm)[3]
Perihelion	2.199 AU (329.009 Gm)[4][3]
Semi-major axis	2.680 AU (400.859 Gm)[4][3]
Eccentricity	0.17924[4][3]
Orbital period (sidereal)	4.39 yr (1,602.14 d)[3]
Average orbital speed	18.19 km/s
Mean anomaly	169.01173°[4]
Mean motion	0° 13m 28.917s / day[4]
Inclination	5.75625°[4][3]
Longitude of ascending node	156.91554°[4]
Argument of perihelion	180.90559°[4]
Jupiter MOID	2.23013 AU (333.623 Gm)[3]
TJupiter	3.347[3]
Physical characteristics
Dimensions	68.39±3.5 km[2] 87.72 km[5]
Synodic rotation period	3.7474 h (0.15614 d)[3]
Geometric albedo	0.1604±0.018[2] 0.0881±0.0187[5]
Spectral type	Tholen = M[5] SMASS = X[3] B–V = 0.720[3] U–B = 0.233[3]
Absolute magnitude (H)	8.38[3] 8.43[2] 8.5[4] 8.54[5]

Based upon the spectra of this object, it is classified as a M-type asteroid, indicating it may be metallic in composition.^[5] It may be the remnant of the core of a larger, differentiated asteroid. Near infrared absorption features indicate the presence of variable amounts of low-iron, low-calcium orthopyroxenes on the surface. Trace amounts of water is detected with a mass fraction of about 0.13–0.15 wt%.^[6] It has an estimated size of around 88 km.^[5] With a rotation period of 3.74 hours, it is the fastest rotating asteroid larger than 50 km in diameter.^[2]