1. Planets

    Icy Orbs at the Solar System’s Edge

    A ring at the solar system's outskirts appears to contain smaller objects than expected.

  2. Planets

    A very distant planet says “cheese”

    A small red spot may be the first picture ever taken of a planet outside the solar system.

  3. Planets

    Planet Hunters Nab Three More

    Astronomers have spotted three Neptune-size planets outside our solar system.

  4. Planets

    Saturn’s New Moons

    The Cassini spacecraft has found evidence of lightning and two tiny moons orbiting the ringed planet.

  5. Planets

    Ringing Saturn

    The Cassini spacecraft has arrived at Saturn to start exploring the planet and its rings and moons.

  6. Planets

    Witnessing a Rare Venus Eclipse

    On June 8, Venus will cross in front of the sun for the first time since 1882.

  7. Planets

    Search for a Missing Moon

    Sedna, the most distant object known in the solar system, doesn't appear to have a moon.

  8. Planets

    Planets on the Edge

    The discovery of a strange, planetlike object beyond Pluto adds to the puzzle of how the solar system formed.

  9. Planets

    Rover Makes Splash on Mars

    A robot on Mars has gathered evidence that liquid water once flowed on the Red Planet.

  10. Planets

    Roving the Red Planet

    Two little robots have touched down on Mars, ready to study the planet's rocks and soil.

  11. Planets

    Catching a Comet’s Tail

    A closeup visit by a NASA spacecraft helps show how a comet gets its shape.

  12. Earth

    Killer space rock snuffed out ancient life

    Rock fragments from Antarctica suggest a huge meteor struck Earth 250 million years ago.