Pluto and the Kuiper Belt

Discovery of Pluto

• Discovered due to irregularities in the orbits of Uranus and Neptune.
• Percival Lowell was instrumental in predicting Pluto's position and calculating its size and orbit.
• Lowell's predictions were off by 6 degrees from Pluto's actual position.

Distance from the Sun

• Pluto is located approximately 40 Astronomical Units (AUs) from the Sun.
• Its distance makes detailed imaging challenging until advancements in technology, leading to New Horizons' flyby in 2015.

Pluto’s Moon: Charon

• Charon is Pluto's most significant moon, measuring 600 km in diameter.
• Charon has the largest size ratio compared to its parent planet among known moons (Pluto-Charon system properties).
• Other notable moons of Pluto include Hydra and Nix.

The Kuiper Belt

• Pluto is a prominent object in the Kuiper Belt, a region located beyond Neptune.
• Owing to improving technology, astronomers have identified over 1,200 objects past Neptune in the Kuiper Belt.
• The Kuiper Belt primarily consists of icy bodies and has about 100 times the mass of the Asteroid Belt due to its icy composition.

Classification of Pluto

• Pluto is classified as a dwarf planet based on recent criteria:
  • Orbits the sun
  • Sufficient mass to be round
  • Has cleared its orbital path
• The classification of dwarf planets has caused controversy among astronomers, leading to mixed opinions regarding Pluto's status.

Plutoids

• An additional classification called 'plutoid' includes icy dwarf planets located beyond Neptune.

Other Dwarf Planets

• Key examples of other dwarf planets include:
  • Quoar: 1,200 km across, larger than Ceres, the largest asteroid.
  • Haumea & Makemake: Ranging from 1,500 to 2,000 km in diameter.
  • Eris: Larger than Pluto.
  • Sedna: The furthest known object in our Solar System, located at the inner edge of the Oort Cloud, with a diameter of 1,500 km and a highly elliptical orbit.