50 Years Ago

  1. A photo of a remotely operated vehicle exploring the Mariana Trench. It appears as a cube hovering over a lighter blue patch surrounded by darkness.

    50 years ago, researchers discovered a leak in Earth’s oceans

    An analysis of oceanic rocks hinted that ocean water drains into Earth’s mantle. How much makes it back into the ocean remains unclear.

  2. A photo of the Golden Record and its cover from the Voyager spacecraft.

    50 years ago, Earth’s chances of contacting E.T. looked slim

    In 1973, a researcher calculated that it could take millions of years to contact aliens. But that hasn’t stopped scientists from trying.

  3. photo of a seal with a plastic bottle in the ocean

    50 years ago, scientists discovered the Great Pacific Garbage Patch

    In 1973, plastic bottles adrift in the North Pacific alarmed scientists. Fifty years later, more than 1.8 trillion pieces of plastic litter the area.

  4. a photo of human footprints in rock

    50 years ago, scientists debated when humans first set foot in North America

    In 1973, archaeologists debated when people first arrived in the Americas. Mounting evidence suggests its much earlier than they thought.

  5. an illustration of a DNA helix with hands inserting missing peices on either side

    50 years ago, scientists sequenced a gene for the first time

    Within five decades, scientists went from sequencing a single gene to sequencing the entire human genome.

  6. Apollo astronaut Harrison “Jack” Schmitt collects moon samples

    Humans haven’t set foot on the moon in 50 years. That may soon change

    In 1972, the era of crewed missions to the moon came to an end. Fifty years later, a new one has begun.

  7. Physics

    50 years ago, physicists found the speed of light

    In the 1970s, scientists set a new maximum speed limit for light. Fifty years later, they continue putting light through its paces.

  8. Several people hold up glasses of beer in a cheers motion
    Health & Medicine

    50 years ago, a ‘cure’ for intoxication showed promise

    In 1972, vitamin and chemical injections reduced the amount of time that rats fed alcohol spent drunk. The science has yet to pan out for people.

  9. A photo of Stonehenge at sunset

    50 years ago, Stonehenge’s purpose mystified scientists. It still does

    In 1972, scientists thought Stonehenge may have been a calendar. Today, we still don’t know its purpose, but we have gained insight on its origin.

  10. Oil from the Deepwater Horizon disaster floats atop the Gulf of Mexico

    50 years ago, scientists found a new way to clean up oil spills

    In the 1970s, researchers added chemicals to the list of oil spill cleanup methods. Soon, they may add microbes.

  11. Image of Pangaea

    50 years ago, scientists dug into Pangaea’s past lives

    In 1972, scientists wondered whether Pangaea was Earth’s only supercontinent. Fifty years later, we know it wasn’t the first and it won’t be the last.

  12. an illustration of the internal structure of a proton
    Particle Physics

    50 years ago, physicists got a whiff of what glues together protons

    In 1972, particle smashups hinted at the gluon, which we now know not only holds together the innards of the proton, but also makes up more than a third of its mass.