Introduced in 1960 by the physicist Freeman Dyson, the famous sphere that bears his name has ignited our imagination. Both the sphere itself and its later variants are key elements in many science fiction works. However, the big question is... can we? Will humanity be able to reach a level that allows us to build something like a Dyson sphere? Even if we only obtain a minimal percentage of the Sun's energy, that would change us forever as a civilization, but the obstacles are, literally, of planetary scale...
The Energy History of Humanity
The discovery of fire completely altered our evolution. First we used leaves, branches, and dry grass. Then we made use of wood in greater volume. We discovered coal and natural gas, harnessed the power of oil, split the atom, and now we are moving toward fusion, but we are also looking upward. The energy history of humanity is fascinating, and its next great chapter involves our mother star, the Sun. Solar panels and solar farms are multiplying, and efficiency is on the rise, but in the very distant future, our relationship with the Sun will need to be much closer if we want to leave Earth. A possible solution was revealed in 1960, and beyond its spectacular requirements, we return to it again and again: The Dyson Sphere
Solid Sphere vs. Dyson Swarm
Despite what some science fiction works like Star Trek: TNG and the game Freelancer taught us, the design of a solid Dyson sphere is not the most recommended due to the risk of impacts, leading to loss of stability and its collapse toward the Sun. The alternative is a Dyson swarm, composed of the largest network of satellites in the galaxy, and possibly the universe. Assuming each collection unit measures one square kilometer, to envelop the Sun we would need 30,000 billion (our billions). Now, where does the material to build them come from? We are a bit lucky, because the answer lies in Mercury. Its advantage is double: on one hand, it is very close to the Sun (which reduces transport distances), and on the other, it is very rich in metals. In short, our Dyson swarm requires devouring Mercury.
https://old.neoteo.com/como-colonizar-la-luna/Building the Swarm
And what about energy? Well, efficiency will be a critical factor. The design of a Dyson swarm demands exponential growth, that is, each satellite should provide enough energy to build another. First one, then two, then four, eight, and so on. The legend of chess and the grains of rice, in satellite version. If all infrastructure problems are solved, there are no efficiency losses, no accidents, no delays, the estimated construction time would not be so extreme. Calculating one month per square kilometer of collectors, the swarm would be ready in a decade. Of course, these are simple numbers, and the current state of humanity makes us doubt any ambitious future... but it is not impossible.
