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.

The Sun is the largest object in our solar system. Its diameter is about 865,000 miles (1.4 million kilometers). Its gravity holds the solar system together, keeping everything from the biggest planets to the smallest bits of debris in orbit around it.

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.

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.

2024年5月7日 · Jupiter is the fifth planet from the Sun, and the largest in the solar system – more than twice as massive as the other planets combined.

theory about the beginnings of the sun and planets. This theory explains that our solar system began as a spinning cloud of gas and dust about 4.5 billion years ago. This cloud was mostly made of atoms of hydrogen and helium with very small amounts of heavier elements. Gravity made the cloud contract, causing the atoms to get closer together and

Saturn and Jupiter are unrivaled in our solar system for the sheer number of moons captured in their orbits. NASA's Solar System Exploration Website tells the story of each of Saturn's moons in detail.

Dwarf planet Ceres is the largest object in the asteroid belt between Mars and Jupiter, and it's the only dwarf planet located in the inner solar system. It was the first member of the asteroid belt to be discovered when Giuseppe Piazzi spotted it in 1801.

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.

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.