Planet Compare - NASA Solar System Exploration
Oct 21, 2025 · 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
Oct 21, 2025 · Pluto was once our solar system's ninth planet, but has been reclassified as a dwarf planet. It's located in the Kuiper Belt.
Mars By the Numbers - NASA Solar System Exploration
Oct 21, 2025 · Mars is the fourth planet from the Sun, and the seventh largest. It’s the only planet we know of inhabited entirely by robots.
In Depth | Moons – NASA Solar System Exploration
Of the terrestrial (rocky) planets of the inner solar system, neither Mercury nor Venus have any moons at all, Earth has one and Mars has its two small moons. In the outer solar system, the gas giants Jupiter …
In Depth | Sun – NASA Solar System Exploration
Its gravity holds the solar system together, keeping everything from the biggest planets to the smallest bits of debris in orbit around it. Even though the Sun is the center of our solar system and essential …
Design a scale model Solar System for public display. Describe the characteristics of the Solar System that make construc-tion of a good scale model so difficult.
In Depth | Our Solar System – NASA Solar System Exploration
Our solar system consists of our star, the Sun, and everything bound to it by gravity – the planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune; dwarf planets such as Pluto; …
MERCURY Although Mercury is extremely close to our Sun, there are other solar systems with multiple planets orbiting even closer to their stars. Mercury is the smallest of our solar system’s major planets …
In Depth | Uranus Moons – NASA Solar System Exploration
Miranda, the innermost and smallest of the five major satellites, has a surface unlike any other moon that's been seen. It has giant fault canyons as much as 12 times as deep as the Grand Canyon, …
In Depth | Proteus – NASA Solar System Exploration
Circling the planet in the same direction as Neptune rotates, Proteus remains close to Neptune's equatorial plane. Proteus is one of the darkest objects in our solar system.