Orbital Rings

What Hacker News said

Strong rec K0SM0S · 2019-10 · on “NASA aims for first manned SpaceX mission in first-quarter 2020”

This is totally right. You might really like Isaac Arthur on YouTube if you don't know him already. "Orbital rings" [1] in his "Upward Bound" series might be just right your alley. Of course, there's so much more he produced, it's even hard to keep up. I personally dream of some "Megastructures" he suggests... Actually already began myself to think of a Dyson Swarm around Earth (for starters) which could then serve as a positional basis for future orbital rings. He really inspired me to think bigger, now. [1]: [this video]

Recommends mtgx · 2018-09 · on “Japan starts space elevator experiments”

Isaac Arthur thinks an orbital ring is a better idea: [this video] He has other videos on ways we could get into space more cheaply, including by space elevators (which he basically doesn't think are feasible).

Recommends mLuby · 2019-09 · on “A Lunar Space Elevator Is Feasible and Inexpensive, Scientists Find”

Lot of talk about how 1. a Moon elevator is pointless without an Earth elevator, and 2. we can't build an Earth elevator with today's technology. However we can build an orbital ring around Earth with today's technology, and it'd be much better than space elevators. [Video] [this video] [Paper] [LINK]

Recommends cletus · 2020-05 · on “Why We Don't Shoot Earth's Garbage into the Sun (2019)”

Weird, I didn't find the term "delta-V" anywhere in the article. Most on HN probably know this but delta-V is the change in velocity required to reach some goal. Fun fact: it requires more delta-V to hit the Sun than it does to leave the Solar System. For giggles, here's a delta-V map of the Solar System [1]. Of course there's the issue of getting things off Earth to begin with but even if you take that as (economically) solvable the detla-V problem remains. Site note: there are lots of proposals for cheaper LEO solutions (in $/kg terms). Probably the most famous is the space elevator but that's actually a bad solution for many reasons and possibly not even feasible since we'd have to invent

Recommends cletus · 2022-03 · on “Impulse Space is betting on a future where launch is cheap”

For another view on how this will change things, consider the delta-V map of the Solar System [1]. As an example you need 45km/s to reach Saturn, roughly 20% of that is just spent getting to Low Earth Orbit. Now consider the long-term trend in the payload cost (by weight) of getting to LEO [2]. This is why people such as myself are so bullish on spaceX (despite quite reasonable qualms about Elon Musk as a person). The impact this has had and will continue to have on reducing this number cannot be overstated. But all of this are still interim steps and we can potentially get the payload to LEO cost under $10/kg. If you want to go down the rabbit hole of this, I strongly recommend Isaac Arthur

Recommends cletus · 2022-10 · on “Space-based solar power is getting serious”

Here is my hope (and my belief): the ultimate end here is orbital rings [1]. To summarize the video, you can put copper cabling in orbit, run a current through it and keep things in place (relative to a point on Earth) with magnetic levitation. The most important part of this is that you can have things in LEO that are fixed to Earth points. Why does this matter? No longer do you have to speed up to Mach 30 to reach orbital speeds. You could technically run a cable from 150km up and carry people and goods from Earth into LEO and back. This could revolutionize long-distance travel on Earth too. It's estimated that a space-based power collector could create about ~7 times the energy of an Eart

Cites erasemus · 2017-12 · on “Maintenance often matters more than innovation (2016)”

Civilisation is a Red Queen; we must keep running just to stand still. Maintaining and conserving things is the job of conservatives, not entrepreneurs, and conservatives resist change. Indeed most changes are detrimental. Yet in the long run we absolutely depend on change in order to adapt and survive. Therefore there has to be a rigorous way of reconciling these two principles. Without fudging ('maintenance often matters more...') Maybe: visionaries will develop new ideas with no intention to enact them . Eventually a few will become so well-thought-out, so vivid and so blatantly superior to the incumbent alternatives that they become inevitable. That is, society cannot help but enact them

Cites stephengillie · 2018-08 · on “France approves 720MW of solar as price falls another 5%”

Electricity transmission would be a foundational part of an orbital ring around Earth. And around a dynamo like Uranus, it could be used to generate electricity too. This (long) video about orbital rings brings such things to mind. [this video]