S/2015 (136472) 1

Also known as MK2, Haua

only known natural satellite of the dwarf planet Makemake

Key facts

Discovered by: HST / Wide Field Camera 3 Alex H. Parker Marc W. Buie William M. Grundy Keith S. Noll
Discovery date: 27 April 2015
Alternative names: MK 2 (unofficial nickname)
Semi major axis: 22 250 ± 780 km
Eccentricity: ≈0
Orbital period sidereal: 18.023 ± 0.017 days
Inclination: 83.7° wrt Earth line of sight , 63°–87° wrt ecliptic ( prograde )
Satellite of: Makemake
Mean diameter: ~175 km (4% albedo; best fit) , 175–250 km (2–4% albedo)
Mean radius: 87.5 km
Albedo: 0.04 (best fit) , 0.02–0.04
Absolute magnitude h: 7.89 ± 0.04

Article

S/2015 (136472) 1, unofficially nicknamed MK 2 by the discovery team, is the only known moon of Makemake, a dwarf planet located in the Kuiper belt. It is a dark object about 175 km (110 mi) in diameter, orbiting 22,250 km (13,800 mi) away from Makemake with an orbital period of 18 days. Observations leading to its discovery occurred in April 2015, using the Hubble Space Telescope's Wide Field Camera 3, and its discovery was announced on 26 April 2016.

Physical characteristics