In Depth | Pluto – NASA Solar System Exploration
Discovered in 1930, Pluto was long considered our solar system's ninth planet. But after the discovery of similar intriguing worlds deeper in the distant Kuiper Belt, icy Pluto was reclassified as a dwarf planet.
Pluto By the Numbers – NASA Solar System Exploration
2025年1月9日 · Pluto was once our solar system's ninth planet, but has been reclassified as a dwarf planet. It's located in the Kuiper Belt.
In Depth | Our Solar System - NASA Solar System Exploration
Our solar system extends much farther than the eight planets that orbit the Sun. The solar system also includes the Kuiper Belt that lies past Neptune's orbit. This is a sparsely occupied ring of icy bodies, almost all smaller than the most popular Kuiper Belt Object – dwarf planet Pluto.
What is a Planet? | Planets – NASA Solar System Exploration
Pluto, discovered in 1930, was identified as the ninth planet. But Pluto is much smaller than Mercury and is even smaller than some of the planetary moons. It is unlike the terrestrial planets (Mercury, Venus, Earth, Mars), or the gas giants (Jupiter, Saturn), or …
Planet Compare - NASA Solar System Exploration
2025年1月9日 · NASA’s real-time science encyclopedia of deep space exploration. Our scientists and far-ranging robots explore the wild frontiers of our solar system.
In Depth | Kuiper Belt – NASA Solar System Exploration
The Kuiper Belt is one of the largest structures in our solar system – others being the Oort Cloud, the heliosphere, and the magnetosphere of Jupiter. Its overall shape is like a puffed-up disk or donut.
In Depth | Eris – NASA Solar System Exploration
Eris is one of the largest known dwarf planets in our solar system. It's about the same size as Pluto but is three times farther from the Sun. At first, Eris appeared to be larger than Pluto.
RPS 3D Viewer - NASA Solar System Exploration
2025年1月9日 · NASA’s real-time science encyclopedia of deep space exploration. Our scientists and far-ranging robots explore the wild frontiers of our solar system.
Pluto By the Numbers – NASA Solar System Exploration
2024年5月16日 · Pluto was once our solar system's ninth planet, but has been reclassified as a dwarf planet. It's located in the Kuiper Belt.
In Depth | Moons - NASA Solar System Exploration
Pluto's large moon Charon is about half the size of Pluto. Like Earth's Moon, Charon may have formed from debris resulting from an early collision of an impactor with Pluto. Scientists using the Hubble Space Telescope to study Pluto found four more small moons.