Feature

  1. Astronomy

    Year in Review: Voyager 1 reaches interstellar space

    The planetary probe is the first human-made object to break out of the heliosphere.

    By Andrew Grant
  2. Health & Medicine

    Year in Review: Putting kids at risk

    U.S. parents increasingly are delaying their children’s vaccination.

    By Nathan Seppa
  3. Climate

    Year in Review: Carbon dioxide levels pass milestone

    Although scientists are confident about humankind’s role in climate change, they still have a lot to learn about the magnitude and timing of future climate shifts.

    By Erin Wayman
  4. Genetics

    Year in Review: Caffeine triggers cloning advance

    To successfully clone human cells, eggs must be dunked in the stimulant.