Planetary Science

  1. Planetary Science

    Deep Impact and Stardust: Still on assignment

    Two sturdy NASA spacecraft have new assignments, studying comets and looking for exoplanets.

    By Ron Cowen
  2. Planetary Science

    G Whiz! Craft identifies source of faint Saturnian ring

    The Cassini spacecraft has discovered the source of particles that make up Saturn's G ring.

    By Ron Cowen
  3. Planetary Science

    Saturn’s retinue: 60 and counting

    A little moon, two kilometers across, is Saturn's 60th satellite.

    By Ron Cowen
  4. Planetary Science

    Hyperion’s hydrocarbons

    New observations by the Cassini spacecraft indicate the presence of ice and solid carbon dioxide on Saturn's moon Hyperion, and suggest an explanation for the orb's spongelike appearance.

    By Ron Cowen
  5. Planetary Science

    Dust delays Martian rover

    A dust storm has delayed the descent of the Mars rover Opportunity into Victoria crater.

    By Ron Cowen
  6. Planetary Science

    Music to alien ears

    Saturn's moon Titan may be the best rock concert venue in the solar system, according to computer simulations of sound propagation on other worlds.

    By Davide Castelvecchi
  7. Planetary Science

    Eris dwarfs Pluto

    Ex-planet Pluto suffers another demotion, as observations show that it's much less massive than Eris, another distant denizen of the outer solar system.

    By Ron Cowen
  8. Planetary Science

    Shifting Ocean: Tipsy Mars may explain undulating shoreline

    Evidence that Mars once had a vast ocean gains support from a proposal that the planet was tipped halfway over on its side several billion years ago.

    By Ron Cowen
  9. Planetary Science

    Powering Enceladus’ plumes

    The action of Saturn's gravity is responsible for plumes of water vapor shooting out from cracks on the moon Enceladus.

    By Ron Cowen
  10. Planetary Science

    Violent Past: Young sun withstood a supernova blast

    A big bully pummeled the infant solar system, first by blasting it with a massive wind, then by exploding nearby, driving shock waves into the fledgling solar system and irrevocably altering its chemistry.

    By Ron Cowen
  11. Planetary Science

    Water World: Extrasolar planet is loaded with hot ice

    Astronomers have found a Neptune-size planet outside the solar system that's composed mainly of water solidified under high pressure.

    By Ron Cowen
  12. Planetary Science

    Liquid Center: Mercury has a molten core, radar reveals

    Mercury is hot stuff: It's got a core that's at least partially molten, a new radar study of the planet's spin reveals.

    By Ron Cowen