Editors' note: This article is part of Dear Future, a collaboration between CNET and VICE Motherboard that looks at major innovations -- in robotics, space travel, VR and more -- shaping the world around us.
For the entirety of recorded history, humans have worshipped nuclear fusion. It's gone by different names over the millennia, of course: the Egyptians called it Ra, the Greeks called it Helios, and the Aztecs knew it as Tonatiuh.
Today, most of us know it as the sun, but leading physicists around the world regard it with the same sense of awe as our ancient ancestors. This is not because these physicists believe the sun rides across the sky in a giant reed boat, ready to exact retribution on us mortals at any moment, however. Rather, they know that the sun harbors the secret to a virtually unlimited source of clean energy.
Every second, trillions of hydrogen ions are fusing in the sun's ultradense 27-million-degree core. The crushing weight of the sun's gravity forces the protons of hydrogen atoms so close together that they combine into a heavier atom (helium) and release an enormous amount of energy: a process called nuclear fusion. Even though the natural fusion reactors at the heart of stars are abundant in the universe, this process has been remarkably hard to replicate on Earth. This is because the sun's own gravity is able to contain the ultrahot and ultradense plasma at its core, but trying to contain even small amounts of hydrogen plasma in containers on Earth for a few hundredths of a second has proven to be a difficult challenge for engineers and physicists.
If the processes powering the fusion reactor at the sun's core could be recreated on Earth, it would be one of the most important events in the history of our species. Nuclear fusion power plants could end our dependency on fossil fuels and provide a virtually limitless, highly efficient source of clean energy. They could help end the developing world's energy crisis and help lift them from poverty. They could also change life off Earth, providing power to lunar and Martian colonies, or even interstellar generation ships.
Of course this future assumes that fusion reactors are even possible.
Figuring out how to make a fusion reactor, or a "star in a jar," has been one of the holy grails of physics. It ended up being a more difficult problem than any of the fusion pioneers in the early twentieth century anticipated, which led to a running joke among nuclear physicists: fusion is always 30 years away.
I went to two of the world's leading nuclear fusion research centers, Sandia National Labs in New Mexico and General Fusion outside Vancouver, to see how close we are to bringing the power of the stars down to Earth. In this episode of Dear Future, we explore the experiments that are laying the groundwork for a future of limitless clean energy.
At Sandia, many of the physicists see fusion research as an exploratory science and a phenomenon that we're just beginning to understand. The researchers at General Fusion, however, are not content to keep waiting for fusion and are actively attempting to harness fusion energy for a practical power plant.
Even if neither of these efforts succeed, dozens of other projects employing thousands of scientists around the globe are also in the race to develop a practical source of fusion energy. In the private fusion reactor space, companies such as California-based Tri Alpha and the UK company Tokamak Energy have both been able generate and sustain plasma in their reactors, despite their radically different approaches to driving fusion reactions.
Our fusion future is coming, but, we just don't know when.