3 HN users recommended this explainer3 months2019–2023score 3.5
Years with an HN recommendation, 2007–2026
HN readers point to it as a clear explanation of a theoretical fuel-free propulsion concept from a channel they respect.
Astrophysicist David Kipping presents the halo drive, a proposed way to propel a starship to a good fraction of light speed by gaining energy from a black hole. The video is based on his peer-reviewed paper and explains why energy is the main obstacle to interstellar flight.
“Prof. Kipping is well known for his Cool Worlds youtube channel, which is fantastic.” (HN, 2023)
The halo drive concept is interesting. It uses a beam of light to extract gravity energy from a black hole and use to to maintain acceleration of your ship. Almost no fuel needed because its really just a kind of extreme gravity assist that we’ve been doing since what, the 1970s? [this video]
Explains fuel-free propulsion via a black hole gravity assist.
If you have the technology to reach the nearest binary blackhole ( "you just have to pay the one-time fee of the cost to reach the nearest binary black hole system" , at 16:12 min in this video: [this video] ), you can most likely deal with the mirror/energy harvesting problem as well.
Cites a specific point in the video on travel cost.
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