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  • In Depth | Our Solar System – NASA Solar System Exploration
    The planetary system we call home is located in an outer spiral arm of the Milky Way galaxy 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 Beyond our own solar system, there
  • Planet Compare - NASA Solar System Exploration
    NASA’s real-time science encyclopedia of deep space exploration Our scientists and far-ranging robots explore the wild frontiers of our solar system
  • RPS 3D Viewer - NASA Solar System Exploration
    NASA’s real-time science encyclopedia of deep space exploration Our scientists and far-ranging robots explore the wild frontiers of our solar system
  • 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 and Saturn and the ice giants Uranus and Neptune have dozens of moons
  • 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)
  • Voyage: A Solar - NASA Solar System Exploration
    Lesson Overview It is challenging to design a scale model of the Solar System where the same scale is used to portray not only the physical sizes of the Sun and planets, but also the distances between them Planets are tiny worlds in a vast space In October 2001, the Voyage Scale Model Solar System opened in Washington, DC, displaying a one to ten billion scale of the sizes of the Sun and
  • Directory - NASA Solar System Exploration
    NASA’s real-time science encyclopedia of deep space exploration Our scientists and far-ranging robots explore the wild frontiers of our solar system
  • Callisto - NASA Solar System Exploration
    The discovery led to the understanding that planets in our solar system orbit the Sun, instead of our solar system revolving around Earth Galileo spotted what he thought were bright stars near Jupiter, but eventually figured out that the “stars” were moons orbiting Jupiter The German astronomer Simon Marius may have observed the moons around the same time, but Galileo was the first to


















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