The video discusses the concept of a stellar engine, a hypothetical device that could potentially move our solar system. The narrator explains that the universe is not static, with billions of stars orbiting the galactic center, including our sun, at a distance of around 30,000 light years. This dance of stars is chaotic and unpredictable, which makes our solar neighborhood dangerous.
The narrator then introduces the idea of a stellar engine, a mega structure used to steer a star through the galaxy. Such an engine could be built by an advanced civilization with Dyson sphere-level technology. The narrator discusses two types of stellar engines: the shut-off thruster and the Kaplan thruster.
The shut-off thruster is a giant mirror that reflects up to half of the solar radiation to create thrust and slowly push the sun where we want it to go. The mirror must be kept in the same place, not orbiting the sun, and it would have to be very light and made of micron-thin reflecting foil from materials like aluminum alloys.
The Kaplan thruster, on the other hand, is a large space station platform powered by a Dyson sphere that gathers matter from the sun to power nuclear fusion. It shoots out a very fast jet of particles at nearly one percent the speed of light out of the solar system, while a second jet pushes the sun along like a tugboat.
The narrator explains that the Kaplan thruster requires a lot of fuel, millions of tons per second, which is gathered using very large electromagnetic fields to funnel hydrogen and helium from the solar wind into the engine. The solar wind alone doesn't provide enough fuel, and that's where the Dyson sphere comes in. Using its power, sunlight can be refocused to the surface of the sun, heating small regions to extreme temperatures and lifting billions of tons of mass off the sun. This mass can be collected and separated into hydrogen and helium, which are then burned explosively in thermonuclear fusion reactors.
The
1. Nothing in the universe is static.
2. In the milky way, billions of stars orbit.
3. The galactic center contains some stars similar to our sun.
4. These stars are pretty consistent, keeping a distance of around 30,000 light years from the galactic center.
5. They complete an orbit every 230 million years.
6. This movement is not an orderly ballet, more like a skating rink filled with drunk toddlers.
7. This chaos makes the galaxy dangerous.
8. Our solar neighborhood is constantly changing with stars moving hundreds of kilometers every second.
9. Only the vast distances between objects protect us from the dangers out there.
10. We might get unlucky in the future, encountering a star going supernova or a massive object passing by and showering earth with asteroids.
11. If something like this were to happen, we would likely know thousands if not millions of years in advance.
12. But we still couldn't do much about it unless we move our whole solar system out of the way.
13. To move the solar system, we need a stellar engine, a mega structure used to steer a star through the galaxy.
14. This kind of thing might be built by an advanced civilization with Dyson sphere level technology.
15. The simplest kind of stellar engine is the shut off thruster, a giant mirror.
16. It works on the same principle as a rocket, like rocket fuel, the photons released as solar radiation carry momentum.
17. The basic idea of the shut-off thruster is to reflect up to half of the solar radiation to create thrust and slowly push the sun where we want it to go.
18. In order for the Shkadov thruster to work, it must be kept in the same place, not orbiting the sun.
19. The mirror would have to be very light made of micron thin.
20. Reflecting foil from materials like aluminum alloys.
21. The mirror's shape is important too.
22. Enveloping the sun in a giant spherical shell wouldn't work because that would refocus light back to the sun, heating it up and creating all sorts of unpleasant problems.
23. Instead, we use a parabola which sends most of the photons around the sun and in the same direction which maximizes thrust.
24. To prevent accidentally burning or freezing earth with too much or too little sunlight, the only safe place to build a Shkadov thruster is over the sun's poles.
25. This means we can only move the sun vertically in the plane of the solar system and one direction in the milky way which limits our travel options a bit.
26. For a civilization capable of building a Dyson sphere, this is a relatively simple endeavor, not complicated just very hard to build.
27. At full throttle, the solar system could probably be moved by about a hundred light years over 230 million years.
28. Over a few billion years, it gives us near complete control over the sun's orbit in the galaxy.
29. But in the short term, this might not be fast enough to dodge a deadly supernova.
30. That's why we thought we could do better.
31. So we asked our astrophysicist friend if he could design a faster stellar engine for this video.
32. He did and wrote a paper about it that's been published in a peer-reviewed journal.
33. We're going to call our new stellar engine the Kaplan thruster.
34. It works a lot like a traditional rocket, shoot exhaust one way to push yourself, the other.
35. It's a large space station platform powered by a Dyson sphere that gathers matter from the sun to power nuclear fusion.
36. It shoots out a very fast jet of particles at nearly one percent the speed of light out of the solar system.
37. A second jet pushes the sun along like a tugboat.
38. The Kaplan thruster requires a lot of fuel, millions of tons per second.
39. To gather this fuel, our thruster uses very large electromagnetic fields to funnel hydrogen and helium from the solar wind into the engine.
40. The solar wind alone doesn't provide enough fuel though and that's where the Dyson sphere comes in