Planetary Science

  1. Planetary Science

    Another red spot, by Jove

    Jupiter has developed a second red spot, which is now visible in the predawn sky with a telescope 10 inches or larger.

    By Ron Cowen
  2. Planetary Science

    Propelling Evidence: Cassini finds clues to source of Saturn’s rings

    Four propeller-shaped gaps in one of Saturn's main rings are the latest evidence that a shattered moon produced the planet's dazzling hoops.

    By Ron Cowen
  3. Planetary Science

    Pluto’s posse

    Images taken by the Hubble Space Telescope on Feb. 15 confirm that Pluto has two small, previously unknown moons.

    By Ron Cowen
  4. Planetary Science

    Eyeing a Saturn storm

    The Cassini spacecraft recently captured an image of the most powerful storm ever seen on Saturn.

    By Ron Cowen
  5. Planetary Science

    Stellar passage yields Charon’s girth

    By observing Pluto's moon Charon passing in front of a star, astronomers have obtained precise measurements of the moon's radius and density.

    By Ron Cowen
  6. Planetary Science

    One star better than two?

    Rather than disrupting the planet-forming process around another star, a nearby companion may sometimes enhance it, new computer simulations suggest.

    By Ron Cowen
  7. Planetary Science

    Moon spray

    The Cassini spacecraft has found conclusive evidence that the south pole of Saturn's moon Enceladus spews jets of icy particles into space.

    By Ron Cowen
  8. Planetary Science

    Red Planet Express: Mars spacecraft traces a watery tale

    A Mars-orbiting spacecraft has provided new details about when and where liquid water existed on the planet.

    By Ron Cowen
  9. Planetary Science

    Martian dust storm

    In late October, a day after Mars and Earth were at their closest approach until 2018, the Hubble Space Telescope captured an image of a large dust storm on the Red Planet.

    By Ron Cowen
  10. Planetary Science

    Found and lost

    Astronomers who previously announced that they had identified the likely remains of the Mars Polar Lander in images taken by an orbiting spacecraft now say that they were fooled by electronic noise in those images.

    By Ron Cowen
  11. Planetary Science

    Mars or Bust!

    Scientists are working to overcome the biomedical challenges that would hinder a human voyage to Mars.

    By Katie Greene
  12. Planetary Science

    Cassini snaps icy moon Dione

    Saturn's small moon Dione has a heavily-cratered, fractured surface.

    By Ron Cowen