Makemake

• Region: Kuiper Belt
  
  

• Diameter: ~1,430 km
  
  

• Mass: 3 × 10²¹ kg
  
  

• Orbit: 306 Earth years, semi-major axis ~45.8 AU, eccentricity 0.16
  
  

• Rotation: ~7.77 hours
  
  

Surface & Geology:
Makemake’s surface is bright and reddish due to methane ice mixed with organic tholins. Minor nitrogen and ethane ices are present. Its surface appears relatively smooth with few large impact features observable via telescopes.

Atmosphere:
No permanent atmosphere has been detected, though a transient atmosphere may form during perihelion as methane sublimates.

Moon:

• MK2: Small moon discovered in 2016, dark, aiding in mass estimation of Makemake.
  
  

Internal Structure:
Probably differentiated into a rocky core and icy mantle. Slight internal heat may exist but is insufficient for geological activity detectable from Earth.

Temperature:
Surface ~–239°C, extremely cold, maintaining volatile ices.

Discovery:
Discovered in 2005 by Michael Brown et al., Makemake helped define the range of large Kuiper Belt dwarf planets.