Planetary Science

  1. Planetary Science

    Sun grazers: A thousand comets and counting

    An amateur astronomer analyzing images from the Solar and Heliospheric Observatory has found the 999th and 1,000th comets detected by the craft.

  2. Planetary Science

    Fresh Mars: Craft views new gullies, craters, and landslides

    A comparison of images taken just a few years apart by a Mars orbiting spacecraft reveals recent landslides, freshly carved gullies, and a 20-meter-wide crater gouged in the planet's surface no earlier than 25 years ago.

  3. Planetary Science

    Icy world found inside asteroid

    New observations of Ceres, the largest known asteroid, hint that frozen water may account for as much as 25 percent of its interior.

  4. Planetary Science

    Top of the Martian hill

    After a 14-month climb up a Martian hill, NASA's rover Spirit took a panoramic image of the view from the top.

  5. Planetary Science

    Satellites could detect quakes on Venus

    Strong seismic activity on Venus could cause brief but detectable temperature increases high in that planet's atmosphere.

  6. Planetary Science

    Radar for rovers on future Mars trips?

    Scientists are developing ground-penetrating radar equipment that could serve as geologists' helpers on future Mars-roving vehicles.

  7. Planetary Science

    Enceladus: Small but feisty

    Close-up observations of Saturn's tiny moon Enceladus reveal that its south pole is hotter than its equator and that the icy satellite continues to undergo eruptions.

  8. Planetary Science

    Bigger than Pluto: Tenth planet or icy leftover?

    Astronomers have found a body larger and more distant than Pluto, the biggest object found in the solar system since Neptune and its moon Triton were discovered in 1846.

  9. Planetary Science

    Cassini eyes youthful-looking Saturnian moon

    On July 14, the Cassini spacecraft came within 175 kilometers of the south polar region of Saturn's bright, tiny moon Enceladus, revealing a tortured terrain of faults, folds, and ridges.

  10. Planetary Science

    A Grand Slam

    A 372-kilogram copper projectile released from NASA's Deep Impact spacecraft successfully slammed into Comet Tempel 1 on July 4, producing some heavenly fireworks.

  11. Planetary Science

    Pebbles from Heaven: Tracking planets in the making

    Recording radio waves from the region around a young star, astronomers have for the first time documented the making pebbles, a key step in the rocky road to planethood.

  12. Planetary Science

    Flashy news from Mars

    A streak across the Martian sky observed by the rover Spirit was most likely a meteor associated with a comet called Wiseman-Skiff.