How to Move the Sun: Stellar Engines
Why Hacker News recommends it
HN returns to it whenever moving the solar system, Kardashev civilizations or generation ships come up, with some calling it their favorite Kurzgesagt video.
What it is
Kurzgesagt explains stellar engines such as the Shkadov thruster and Caplan thruster, which could move the Sun and solar system across the galaxy over millions of years to avoid hazards and reach new regions.
Recommended by 3 HN commenters across 4 different months, 2020 to 2025.
What Hacker News said
Strong rec Diti · 2021-05 · on “Kardashev Scale”
Out of every video Kurzgesagt has ever produced, my favorite is this one, which talks about a stellar engine that a type Ⅱ civilization could be using: [this video]
Strong rec gcanyon · 2024-02 · on “Grabby Aliens (2021)”
In case anyone is interested in how grabby aliens (or we!) could travel the galaxy, Kurzgesagt has an excellent video on building a stellar engine to move our solar system at up to 50 light years per million years. Setting aside considerations of whether we'll survive the next few decades as a technological civilization, let alone the next few millions of years, the Caplan engine would let us colonize a significant fraction of the galaxy within a billion years or so. [this video]
Recommends Darmody · 2020-08 · on “Spaceship Earth”
And how do we move our spaceship? I was amazed to know that theoretically we can move our solar system. [this video]
Recommends gcanyon · 2025-10 · on “Flies keep landing on North Sea oil rigs”
You might enjoy Kurzgesagt's video on moving the Sun (and with it the whole solar system) they propose a method that would theoretically let us colonize the galaxy in a reasonable (but not trivial) time frame. To your exact point though, since we're moving the whole solar system, everyone would be living their whole lives on the/a ship. [this video]
Cites solarengineer · 2020-01 · on “The Caplan Thruster – approach to move an entire solar system”
Extracts: The machine would use a Dyson sphere to collect mass, separate out helium to push the sun, and fire hydrogen at the sun to avoid crashing into the sun. It could push the Sun at a speed of about 50 light years per one million years. Matthew Caplan from Illinois State University designed the machine at the behest of Munich-based YouTube channel Kurzgesagt. The channel then created a stunning video to illustrate the device, which it dubbed the Caplan Thruster, and a paper Caplan wrote describing the machine has also been published in the journal Acta Astronautica. Video links: Kaplan thruster: [this video] Dyson sphere: [LINK]
Cites mLuby · 2021-05 · on “Wormhole Tunnels in Spacetime May Be Possible, New Research Suggests”
I wouldn't expect an exhaust plume passing through a wormhole to move the wormhole itself (or the heavily curved "portals" at its ends) any more than a plume would move "flat"/"normal" spacetime. Separately, Kurzgesagt did a video on stellar engines (which can be much less exotic than wormholes); sounds like what you're describing: [this video]
Cites billytetrud · 2023-12 · on “Particle Life”
Saying there is "no evidence" is factually absurd. There are a whole host of possibilities for practical long distance space travel. At very least for small light-weight robots. And it even seems possible that we can viably transport our entire solarsystem: [this video] . No evidence indeed... only if you lack imagination.
Cites gcanyon · 2024-03 · on “Doubts grow about the biosignature approach to alien-hunting”
Here's the Kurzgesagt video on moving the solar system through the galaxy: [this video] I've seen at least one "physicist reacts" video to this that tl;dw's to: "seems reasonable, would obviously require a lot of technological advancement and work"