Haumea is a unique and intriguing dwarf planet in the Kuiper Belt, characterized by its elongated shape, rapid rotation, and icy surface. With its two moons and distinctive features, Haumea offers valuable insights into the nature of outer Solar System objects and the dynamics of icy bodies in distant regions.

1. 1. Size and Shape

• • • Diameter: Haumea is approximately 1,632 km (1,014 miles) across at its longest axis and about 1,063 km (661 miles) across at its shortest axis. This makes it one of the largest known dwarf planets.
    • Shape: Haumea is not spherical but rather elliptical or elongated due to its rapid rotation. It is significantly stretched along its equatorial axis, giving it an oval shape rather than a round one.

 

1. 2. Rotation and Orbit

• • • Rotation: Haumea has an extremely rapid rotation period, completing one rotation approximately every 4 hours. This rapid spin is responsible for its elongated shape.
    • Orbit around the Sun: Haumea orbits the Sun in a highly elliptical orbit that takes about 285 Earth years to complete. Its orbit ranges from about 35 AU at perihelion (closest approach to the Sun) to about 51 AU at aphelion (farthest distance from the Sun).

 

1. 3. Surface and Composition

• • • Surface Features: Haumea’s surface is covered with water ice, giving it a bright, reflective appearance. Its icy surface suggests it is composed largely of water ice with some rock.
    • Composition: Haumea is thought to have a rocky core surrounded by a thick layer of ice. The bright, icy surface and high reflectivity are due to its water ice composition.

 

1. 4. Moons

• • • Hiʻiaka: The larger of the two, Hiʻiaka has a diameter of about 320 km (199 miles) and orbits Haumea at approximately 49,500 km (30,800 miles). It was discovered in 2005.
    • Namaka: The smaller moon, Namaka has a diameter of about 150 km (93 miles) and orbits Haumea at approximately 40,000 km (25,000 miles). It was discovered in 2005 as well.
    • Both moons are thought to be icy bodies like Haumea, and their discovery has provided additional insight into Haumea’s system.

 

1. 5. Temperature

Haumea is extremely cold, with surface temperatures estimated to be around -223°C (-369°F). Its low temperatures are a result of its distance from the Sun and its reflective icy surface.

 

1. 6. Discovery and Naming

• • • Discovery: Haumea was discovered in 2004 by a team led by Mike Brown, though it was officially announced in 2006. Its discovery was significant in the context of defining and classifying dwarf planets.
    • Naming: Haumea is named after the Hawaiian goddess of fertility and childbirth. The name reflects the object’s connection to Hawaiian mythology and the discoverers’ heritage.

 

1. 7. Interior Structure

Haumea likely has a rocky core surrounded by a thick icy mantle. Its rapid rotation and elongated shape suggest that it has undergone significant internal stresses, which have affected its structure.

 

1. 8. Orbital Characteristics

• • • Eccentricity: Haumea’s orbit is somewhat eccentric, meaning it deviates from a perfect circle. This results in variations in its distance from the Sun, affecting its temperature and other physical conditions.
    • Inclination: Haumea’s orbit is also tilted relative to the plane of the Solar System, which adds to its unique orbital dynamics.

 

1. 9. Scientific Significance

Haumea’s rapid rotation and elongated shape provide insights into the effects of rotational forces on icy bodies in the Kuiper Belt. Its dual moon system also offers valuable data about the formation and evolution of such systems in the outer Solar System.

 

1. 10. Interesting Facts

• • • Elliptical Shape: Haumea’s shape is a direct result of its rapid rotation, which causes it to bulge at the equator and flatten at the poles.
    • High Reflectivity: Haumea’s surface reflects about 70% of the sunlight that hits it, making it one of the brightest objects in the Kuiper Belt.
    • Unique Classification: Haumea’s combination of an elongated shape, rapid rotation, and dual moon system makes it a particularly interesting object for studying the dynamics and characteristics of distant icy bodies.