(574372) 2010 JO179

(574372) 2010 JO₁₇₉ (provisional designation 2010 JO₁₇₉) is a large, high-order resonant trans-Neptunian object in the outermost regions of the Solar System, approximately 700 kilometers (430 miles) in diameter.^[6] Long-term observations suggest that the object is in a meta-stable 5:21 resonance with Neptune.^[6] Other sources classify it as a scattered disc object.^[4][5] It is possibly large enough to be a dwarf planet.^[6]

(574372) 2010 JO₁₇₉

Discovery[1][2]
Discovered by	Pan-STARRS 1
Discovery site	Haleakala Obs.
Discovery date	10 May 2010
Designations
MPC designation	(574372) 2010 JO179
Alternative designations	2010 JO179
Minor planet category	TNO[3] · SDO[4][5] · 5:21 res.[6] p-DP · distant[1]
Orbital characteristics[3]
Epoch 31 May 2020 (JD 2459000.5)
Uncertainty parameter 2
Observation arc	69.54 yr (25,399 days)
Earliest precovery date	4 February 1951 (POSS-I)[1]
Aphelion	117.997 AU
Perihelion	39.590 AU
Semi-major axis	78.793 AU
Eccentricity	0.49755
Orbital period (sidereal)	699.43 yr (255,466 d)
Mean anomaly	35.211°
Mean motion	0° 0m 5.04s / day[3]
Inclination	32.025°
Longitude of ascending node	147.350°
Time of perihelion	1951-Sep-13[7]
Argument of perihelion	10.427°
Physical characteristics
Mean diameter	597 km[8] 735 km[4] 600–900 km[6]
Synodic rotation period	30.6 h[6] 30.6324 h (best fit)[6]
Geometric albedo	0.07 ~ 0.21 (estimated)[6] 0.10 (assumed)[8] 0.09 (assumed)[4]
Spectral type	g-r = 0.88±0.21 r-i = 0.34±0.26 r-z = 0.13±0.22[6]
Absolute magnitude (H)	3.44±0.10 (R-band)[6] 3.86[3] 3.84[1]

First observation and orbit

The libration of 2010 JO₁₇₉'s nominal orbit, in a frame co-rotating with Neptune (click image to view animation)

The Minor Planet Center credits the object's first official observation on 10 May 2010 to Pan-STARRS (F51) at Haleakala Observatory, Hawaii, United States.^[1][2] The observations were made by Pan-STARRS' Outer Solar System Survey.^[6] There are 4 February 1951 precovery images from the Palomar Observatory Sky Survey, extending the observation arc by approximately 60 years.^[1] The precovery images are from the same year the object came to perihelion (closest approach to the Sun).

2010 JO₁₇₉ orbits the Sun at a distance of 39.6–118 AU once every 699 years and 5 months (semi-major axis of 78.8 AU). Its orbit has a high eccentricity of 0.50 and an inclination of 32° with respect to the ecliptic.^[3]

Numbering and naming

This minor planet was numbered by the Minor Planet Center on 10 August 2021, receiving the number 574372 in the minor planet catalog M.P.C. 133504.^[9] As of 2025^[update], it has not been named.^[1]

Physical characteristics

Photometry

Photometric observations of 2010 JO₁₇₉ gave a monomodal lightcurve with slow rotation period of 30.6 hours, suggesting a rather spherical shape with significant albedo patchiness. An alternative period solution of a bimodal lightcurve is considered less likely. It would double the period and imply an ellipsoidal shape with an axis-ratio of at least 1.58.^[6]

Diameter and albedo

The object's mean diameter has been estimated to measure 574 and 735 kilometers, with an assumed albedo of 0.09, by Michael Brown and Johnston's Archive respectively,^[4][8] while the discoverers estimate a diameter of 600–900 kilometers with an estimated albedo of 0.21 to 0.07.^[6]