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 …

A planet is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly …

Scientists think it's likely some other force is responsible, such as an undiscovered giant planet (in a very distant orbit), the gravity of passing stars, or gravitational perturbations as the Kuiper …

No other planet in our solar system has rings as splendid as Saturn’s. They are so expansive and bright that they were discovered as soon as humans began pointing telescopes at the night sky.

Dwarf planet Pluto is a member of a group of objects that orbit in a disc-like zone beyond the orbit of Neptune called the Kuiper Belt. This distant realm is populated with thousands of miniature …

2025年1月9日 · Explore NASA's real-time science encyclopedia and compare the sizes of planets in our solar system.

2025年1月9日 · Mars is the fourth planet from the Sun, and the seventh largest. It’s the only planet we know of inhabited entirely by robots.

2025年1月9日 · Lunar Laser Ranging studies the Moon’s internal structure and properties by tracking the variations in the orientation and tidal distortion of the Moon as a function of time. …

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 …

The planet is nearly as big around as Earth – 7,521 miles (12,104 kilometers) across, versus 7,926 miles (12,756 kilometers) for Earth. From Earth, Venus is the brightest object in the …