Most of the hundreds of billions of stars in our galaxy are thought to have planets of their own, and the Milky Way is but one of perhaps 100 billion galaxies in the universe.

Oct 21, 2025 · NASA Solar System Exploration Our Galactic Neighborhood Solar System Planets Moons Asteroids, Comets & Meteors More

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 …

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.

Europa orbits Jupiter at about 417,000 miles (671,000 kilometers) from the planet, which itself orbits the Sun at a distance of roughly 500 million miles (780 million kilometers), or 5.2 …

Oct 7, 2021 · REACH: A Space Podcast for Kids is a weekly, family friendly exploration of our galaxy (and beyond!) with hosts Brian Holden and Meredith Stepien. Built for kids and based …

Sep 21, 2023 · NASA’s real-time science encyclopedia of deep space exploration. Our scientists and far-ranging robots explore the wild frontiers of our solar system.

Sep 3, 2025 · Facts About Jupiter Jupiter is the largest and oldest planet in our solar system. If Jupiter was a hollow shell, 1,000 Earths could fit inside. But the "King of Planets" is no …

The period varies from appearance to appearance because of the gravitational effects of the planets. Measured from one perihelion passage to the next, Halley's period has been as short …

Dec 4, 2025 · Our solar system includes the Sun, eight planets, five officially named dwarf planets, hundreds of moons, and thousands of asteroids and comets. Our solar system is …