(91133) 1998 HK151

(91133) 1998 HK₁₅₁ (provisional designation 1998 HK₁₅₁) is a resonant trans-Neptunian object from the Kuiper belt, located in the outermost region of the Solar System. It measures approximately 134 kilometers in diameter. It was discovered by astronomers at the Mauna Kea Observatory on 28 April 1998.^[1]

(91133) 1998 HK₁₅₁

Discovery
Discovered by	Mauna Kea Observatory
Discovery date	28 April 1998
Designations
Minor planet category	plutino (TNO)
Orbital characteristics[1]
Epoch 13 January 2016 (JD 2457400.5)
Uncertainty parameter 3
Observation arc	1178 days (3.23 yr)
Aphelion	48.529 AU (7.2598 Tm)
Perihelion	30.347 AU (4.5398 Tm)
Semi-major axis	39.438 AU (5.8998 Tm)
Eccentricity	0.23052
Orbital period (sidereal)	247.67 yr (90462.3 d)
Mean anomaly	25.159°
Mean motion	0° 0m 14.327s / day
Inclination	5.9365°
Longitude of ascending node	50.194°
Argument of perihelion	180.55°
Physical characteristics
Dimensions	134 km (Johnston's archive)
Geometric albedo	0.09 (assumed)
Spectral type	(Blueish;lowest TNO B-V) B-V=0.51; V-R=0.43[2]
Absolute magnitude (H)	7.6

Description

1998 HK₁₅₁ is classified as a plutino, a dynamical group named after Pluto. Members of this group stay in a 2:3 resonance with Neptune.

1998 HK₁₅₁ has the lowest, and thus bluest measured B-V color index of any TNO. On 24 May 2000, 1998 HK₁₅₁ set a TNO record low B-V of 0.51. Reddening of the spectrum is caused by ultraviolet radiation and charged particles. Becoming bluer in the spectrum is caused by impact collisions exposing the interior of an object.

Based on an absolute magnitude of 7.62, 1998 HK₁₅₁, Johnston's Archive estimates a diameter of 134 kilometers, assuming an albedo of 0.09.