• White Holes

    “White Holes” Could Exist—But That Doesn’t Mean They Do

      A black hole is a one-way door to oblivion. According to general relativity, once anything crosses its boundary—the event horizon—it cannot return to the outside. For that particle, the black hole is the entire future. We’ll never actually get a chance to see the particle live out that destiny: Any light the particle emits […]

  • Issue13_HERO


    Some half a billion years ago, the first animals with bilateral symmetry appeared on Earth. Rather than being shapeless or spherical, they had long axes with a “left” and “right.” Their mouths separated from their anuses, allowing their gut to run down the length of their body. Movements became more directed, and nervous systems more […]

  • Grant_HERO

    Two-Stroke Toilets

    The trouble with time travel.

  • Laughlin_HERO

    Third Data Server From the Sun

    The Earth is becoming a computer visible across galactic distance.

  • Powell_HERO

    When the Earth Had Two Moons

    A new model—“The Big Splat”—explains the strange asymmetry of the moon.

  • Zeldovic_HERO_2

    An Expert’s Guide to Celebrity Faces

    The way we process faces means that symmetry is only part of the story.

  • Jabr_HERO

    Half Male, Half Female, Total Animal

    Mixed-sex animals teach us about our own multifarious nature.

  • Steele_HERO_3

    “We Are Visual Animals, Driven By Images”

    The head of the Max Planck Society discusses the science of creative visualization.

  • Gruss_HERO

    Picasso and Einstein Got the Picture

    Breakthroughs in science and art begin with an image.

  • Wald_HERO

    What Do Animals See in a Mirror?

    A controversial test for self-awareness is dividing the animal kingdom.