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  • In Depth | 1P Halley – NASA Solar System Exploration
    The History of Halley's Comet Until the time of English astronomer Edmond Halley (1656-1742), comets were believed to make only one pass through the solar system But in 1705, Halley used Isaac Newton's theories of gravitation and planetary motions to compute the orbits of several comets
  • Asteroids, Comets Meteors - NASA Solar System Exploration
    Asteroids and comets – and the meteors that sometimes come from them – are leftovers from the formation of our solar system 4 6 billion years ago
  • 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
  • Kuiper Belt and Oort Cloud - NASA Solar System Exploration
    The Kuiper Belt should not be confused with the Oort Cloud, which is a thousand times more distant In 1950, astronomer Jan Oort proposed that certain comets come from a vast, extremely distant spherical shell of icy bodies surrounding the solar system This giant swarm of objects, now named the Oort Cloud, occupies space at a distance between 5,000 and 100,000 astronomical units No objects
  • In Depth | Kuiper Belt – NASA Solar System Exploration
    Objects that remain there occasionally collide, producing smaller objects fragmented by the collision, sometimes comets and also dust that's blown out of the solar system by the solar wind Structure and Characteristics The Kuiper Belt represents an enormous, donut-shaped volume of space in the outer 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
  • C 1995 O1 (Hale-Bopp) - NASA Solar System Exploration
    Hale-Bopp last reached perihelion (closest approach to the sun) on Apr 1, 1997 How Comet C 1995 O1 (Hale-Bopp) Got Its Name Comets are usually named for their discoverer (s) or for the name of the observatory telescope used in the discovery Since both Alan Hale and Thomas Bopp discovered this comet it is named for them
  • In Depth | 21P Giacobini-Zinner – NASA Solar System Exploration
    Comets are usually named for their discoverer (s) or for the name of the observatory telescope used in the discovery Since both Michel Giacobini and Ernst Zinner discovered and recovered this comet it is named for them The letter "P" indicates that Giacobini-Zinner is a periodic comet Periodic comets have an orbital period of less than 200




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