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; dozens of moons; and millions of asteroids, comets, and meteoroids.
What is a Planet? | Planets – NASA Solar System Exploration
Defining the term planet is important, because such definitions reflect our understanding of the origins, architecture, and evolution of our solar system. Over historical time, objects categorized as planets have changed.
Planet Compare - NASA Solar System Exploration
Dec 19, 2024 · NASA’s real-time science encyclopedia of deep space exploration. Our scientists and far-ranging robots explore the wild frontiers of our solar system.
Rings | Science – NASA Solar System Exploration
In the 400 years since Galileo's discovery, the rings have become Saturn’s telltale feature and are perhaps the most recognized characteristic of any world in our solar system. Cassini spent more than a decade examining them more closely than any spacecraft has before.
In Depth | Sun – NASA Solar System Exploration
The Sun orbits the center of the Milky Way, bringing with it the planets, asteroids, comets, and other objects in our solar system. Our solar system is moving with an average velocity of 450,000 miles per hour (720,000 kilometers per hour).
In Depth | Moons – NASA Solar System Exploration
There are hundreds of moons in our solar system – even asteroids have been found to have small companion moons. 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 Depth | Hypothetical Planet X - NASA Solar System Exploration
Jan 20, 2015 · Caltech researchers have found mathematical evidence suggesting there may be a "Planet X" deep in the solar system. This hypothetical Neptune-sized planet orbits our Sun in a highly elongated orbit far beyond Pluto.
Mercury By the Numbers – NASA Solar System Exploration
Nov 20, 2024 · Mercury is the closest planet to the Sun, and the smallest planet in our solar system - only slightly larger than Earth's Moon.
Asteroids, Comets & Meteors - NASA Solar System Exploration
Our solar system’s small bodies – asteroids, comets, and meteors – pack big surprises. These chunks of rock, ice, and metal are leftovers from the formation of our solar system 4.6 billion years ago.
Gravity Assist: Ice Giants (Uranus & Neptune) with Amy Simon
Jan 17, 2018 · Beyond Saturn are two of the most misunderstood and bizarre planets in our solar system—the “ice giants” Uranus and Neptune. Did you know that Uranus has rings and appears to spin on its side? And that windy and intensely blue …