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How Dyson Spheres Work


You're So Civilized
Freeman Dyson speaking during the Digital Life Design conference in Munich, Germany in 2012.
Freeman Dyson speaking during the Digital Life Design conference in Munich, Germany in 2012.
©Nadine Rupp/Getty Images

Not all civilizations are the same, at least according to some theories. In the early 1960s, an astrophysicist named Nikolai Kardashev proposed the idea that there may be three classifications of civilization in the universe.

Type I civilizations have learned how to harness all of the energy sources on their home planet. That'd be us. Or at least, someday it might be us. According to theoretical physicist Michio Kaku, we might get to that level in the next century or two.

A Type II civilization understands how to harness all of the energy of the star in its solar system. And Type III civilizations, a status we may reach in several million years, know how to capture and focus the energy of entire galaxies.

We humans are clearly not Type III material just yet. First, we must start with baby steps — by finishing the pillaging of our planet to tap its remaining resources. And then, we'll attempt to shove our way into the more upscale Type II neighborhood by capturing and channeling the immense energy of our sun. This might be doable in the next few thousand years, if we stay alive that long.

In his 1937 book, "Star Makers," author Olaf Stapledon was perhaps the first person to conceive of a so-called "light trap" used to mine the sun's energy. He wrote of energy capture systems so enormous that they actually dimmed the light of the galaxies.

This story is what sparked the mind of Freeman Dyson, a mathematician and theoretical physicist. He began pondering just how possible or impossible it might be to capture all of a star's energy for human use.


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