Uncategorized

  1. Planetary Science

    Galileo finds spires on Callisto

    The sharpest images ever taken of Jupiter's icy moon Callisto show a group of features never seen before on the remote body—icy, knoblike spires that show signs of slow but steady erosion.

    By Ron Cowen
  2. Astronomy

    X rays trace fierce stellar winds

    A high-resolution X-ray view of the Rosette nebula, a nearby star-forming region, has revealed for the first time that the stellar winds from massive stars heat surrounding gas to a scorching 6 million kelvins.

    By Ron Cowen

  3. 18972

    Several key ideas seem missing from “Life on the edge”: 1) the fundamental nature of overpopulation and how it combines with technology to drive mass extinction; 2) the concept of functional extinction, an example being the decimated numbers and diminished range of elephants; and 3) a reasonable extrapolation of human technology.