What is the Kuiper Belt?
A frozen frontier that extends far beyond the last planet.
The answer
The Kuiper Belt is a doughnut-shaped region of icy bodies extending from Neptune's orbit (about 30 AU) to roughly 50 AU from the Sun. It contains hundreds of thousands of objects larger than 100 km, including dwarf planets like Pluto, Eris, and Makemake. These frozen remnants are pristine building blocks from the solar system's formation 4.6 billion years ago. Short-period comets originate in the Kuiper Belt. NASA's New Horizons spacecraft flew through it, visiting Pluto in 2015 and the contact binary Arrokoth in 2019, revealing remarkably complex geology on these distant worlds.
Source: NASA New Horizons
- Kuiper Belt
- Pluto
- solar system
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