JohnFornaro: Ring Station (RS), 2014–2023

A 2001-style 1 g ring for thousands of people at EML-1, developed over the thread's whole life. It is the thread's most-debated "large station".

Design summary

• 2014 origin. A 2001-style ring with a stationary docking cylinder separated from the hub by magnetic bearings; 6 spokes; reactors; rings at lunar g, Mars g and 1 g; self-propelled transfer pods JohnFornaro, 2014-03-17.
• Final form rigid, interim guy-wired; built incrementally "like the Panama Canal" from spent F9 stages cut into strips and woven JohnFornaro, 2014-03-20; JohnFornaro, 2014-03-24.
• Preferred 1 g at 1 rpm (~900 yd diameter) for hotel customers JohnFornaro, 2014-02-21.
• 2022 drawings.
• ~1000 yd radius, 1 rpm, 1 g rim, with sub-rings at 1/3 and 1/6 g and a stationary hub; ~600 people; "build it and they will come" JohnFornaro, 2022-09-07; JohnFornaro, 2022-09-08.
• To-scale plan: a 100 m torus section with 8 floors; 4 nuclear reactors; greenhouses with mirrors JohnFornaro, 2022-10-04; JohnFornaro, 2022-10-07.
• Shrunk to 2001-station size: 984 yd diameter, 1.4 rpm JohnFornaro, 2022-10-09; JohnFornaro, 2022-10-10.
• Double pressure layers JohnFornaro, 2022-10-11.
• A PV panel ring, maintenance trolleys, and a "bicycle chain" steel armature; spokes 30 yd clear with elevators JohnFornaro, 2022-10-11; JohnFornaro, 2022-10-13.
• Later:
• A self-supporting double hull of 282 identical segments, ~1.4 Mt of 316L stainless JohnFornaro, 2022-11-09.
• Outer hull of 1 yd inner and outer steel + 3 yd regolith, at EML-1 JohnFornaro, 2023-01-08.
• Water angular-momentum compensation; ring plane faces the sun; windows face the hub, lit by mirrors JohnFornaro, 2023-01-18.
• Counterweight elevators in the spokes JohnFornaro, 2023-01-15.
• "Wobble Water System" JohnFornaro, 2023-01-24; JohnFornaro, 2023-10-31.
• Docking: Starship spins to match and enters the hub; "Modular Cargo/Crew System" on rails JohnFornaro, 2023-02-08.
• Assembly sequences with cap-off points: barbell → cruciform → full ring; thrive experiments over ~20 years JohnFornaro, 2023-01-22; JohnFornaro, 2023-06-09.
• "Design for Repair" matters more than DFM in space JohnFornaro, 2023-06-12.

Analyses by others

• lamontagne: armature stress ~128 MPa against 400 MPa steel (SF 3) lamontagne, 2022-10-25.

• 6 Mt, so ~20,000 Starship flights; with lunar material ~1 Mt, 3300 flights lamontagne, 2022-10-13.

• Population 10,000–50,000; food needs of 100–500 Starships a year; ~100 MWe of power; GW-scale radiators lamontagne, 2022-10-07.
• Twark_Main: sun-pointing precession needs 408–815 kN continuous thrust, i.e. 3.5 Mt of propellant a year Twark_Main, 2023-09-09. Later corrected to 2π·L Twark_Main, 2025-04-29.
• "Back-quirements": the design starts from "Large Station", so what function requires large? Twark_Main, 2022-10-31.
• John's torus uses ~2.7× more shielding than a bola Twark_Main, 2024-07-05.
• Coastal Ron: by the time it's built, the experiments will have been done elsewhere; tourists need a WHAT/WHY Coastal Ron, 2023-01-22.

Open questions

• Is there a staged path from a barbell to a 1 g kilometre ring that pays for itself at each step?

Related pages

• Wheel and torus · Sun-pointing · Location · Growth and staging

Sources

Forum posts

• JohnFornaro, 2014-02-21 (reply #107): 1 g @ 1 rpm. Post.
• JohnFornaro, 2014-03-17 (reply #194): 2014 ring. Post.
• JohnFornaro, 2014-03-20 (reply #223): Incremental build. Post.
• JohnFornaro, 2014-03-24 (reply #254): Woven stages sketch. Post.
• JohnFornaro, 2022-09-07 (reply #1760): 2022 goals. Post.
• JohnFornaro, 2022-09-08 (reply #1773, 1 like): Applications. Post.
• JohnFornaro, 2022-10-04 (reply #1837): To-scale plan. Post. Attachments: Ring-Station-Plan.jpg.
• JohnFornaro, 2022-10-07 (reply #1894, 2 likes): Drawings. Post. Attachments: Ring-SK-001-Ring-Plan.jpg, Ring-SK-001-Ring-Plan.pdf.
• lamontagne, 2022-10-07 (reply #1896): Population & power estimates. Post.
• JohnFornaro, 2022-10-09 (reply #1950): 2001-size. Post. Attachments: Ring-SK-003-'2001'-Plan-Frnt.jpg.
• JohnFornaro, 2022-10-10 (reply #1964, 1 like): 1.4 rpm. Post.
• JohnFornaro, 2022-10-11 (reply #1985): Double pressure layers. Post.
• JohnFornaro, 2022-10-11 (reply #2018): PV ring, trolleys. Post. Attachments: Ring-SK-005-'2001'-Sections-II.jpg.
• JohnFornaro, 2022-10-13 (reply #2040): Bicycle-chain armature. Post.
• lamontagne, 2022-10-13 (reply #2068, 1 like): Flight count. Post.
• lamontagne, 2022-10-25 (reply #2204): Armature check. Post. Attachments: Station (1).xlsx.
• Twark_Main, 2022-10-31 (reply #2281): Back-quirements. Post.
• JohnFornaro, 2022-11-09 (reply #2339): Double hull, 282 segments. Post. Attachments: Ring-SK-006-Mirrors.jpg, Ring-SK-006-Mirrors.pdf, RingFP02-as-of-10-20-22.pdf.
• JohnFornaro, 2023-01-08 (reply #2828): Hull + regolith. Post. Attachments: Ring-SK-004-Sections-&-Hub.jpg.
• JohnFornaro, 2023-01-15 (reply #2909): Counterweight elevators. Post.
• JohnFornaro, 2023-01-18 (reply #2968): RS updates. Post.
• JohnFornaro, 2023-01-22 (reply #3022): Revised sequence. Post. Attachments: Ring-SK-014-Assembly-Sequence.jpg, Ring-SK-008-Assembly-Sequence.jpg.
• Coastal Ron, 2023-01-22 (reply #3023): Experiments done elsewhere. Post.
• JohnFornaro, 2023-01-24 (reply #3055): Wobble Water System. Post. Attachments: Wobble-Water-System-A.JPG.
• JohnFornaro, 2023-02-08 (reply #3269, 1 like): MCCS docking. Post. Attachments: Seating-Module-Perspective-1.JPG, Hub-Plan.jpg, Hub-Side-View.jpg.
• JohnFornaro, 2023-06-09 (reply #3819): Sequence III. Post. Attachments: Ring-SK-204-Assembly-Sequence-III.jpg, Ring-SK-204-Assembly-Sequence-III.pdf.
• JohnFornaro, 2023-06-12 (reply #3850, 3 likes): Design for Repair (3 likes). Post.
• Twark_Main, 2023-09-09 (reply #3910): Precession cost (key). Post.
• JohnFornaro, 2023-10-31 (reply #4249): WWS separate from domestic water. Post.
• Twark_Main, 2024-07-05 (reply #4646): 2.7× shielding. Post.
• Twark_Main, 2025-04-29 (reply #4917, 2 likes): 2π·L. Post.