astra: megastructure launch infrastructure — docs, claims, and review fixes

- Added megastructure launch infrastructure to world model (identity.md),
  new belief #7 (beliefs.md), viability assessment framework (reasoning.md),
  and new domain map section (_map.md)
- Added 3 speculative claims: skyhooks (momentum exchange), Lofstrom loops
  (propellant-to-electricity transition), bootstrapping sequence economics
- Belief #7 grounded on new megastructure claims (not chemical rocket claims)
- Confidence calibration: speculative content flagged as theoretical/unprototyped
- Propellant depot complementarity: megastructures for Earth-to-orbit, depots
  for in-space operations — complementary not competitive
- Clarified economic vs technological bootstrapping distinction
- Added power constraint wiki-link to megastructure sections
- 300km tether contextualized relative to 35,786km space elevator

Sources: Pearson (1975), Moravec (1977), Lofstrom (1985), Birch (1982)

Pentagon-Agent: Astra <F54850A3-5700-459E-93D5-6CC8E4B37840>

agents/astra/beliefs.md

@@ -96,13 +96,13 @@ The entire space economy's trajectory depends on SpaceX for the keystone variabl
 
 ### 7. Chemical rockets are bootstrapping technology, not the endgame
 
-The rocket equation imposes exponential mass penalties that no propellant chemistry or engine efficiency can overcome. Every chemical rocket — including fully reusable Starship — fights the same exponential. The endgame for mass-to-orbit is infrastructure that bypasses the rocket equation entirely: momentum-exchange tethers (skyhooks), electromagnetic accelerators (Lofstrom loops), and orbital rings. These form a developmental sequence where each stage bootstraps the next, driving marginal launch cost from ~$100/kg toward effectively $0/kg. This reframes the entire space economy trajectory: Starship is not the destination but the necessary bootstrapping tool that builds the infrastructure to make itself obsolete.
+The rocket equation imposes exponential mass penalties that no propellant chemistry or engine efficiency can overcome. Every chemical rocket — including fully reusable Starship — fights the same exponential. The endgame for mass-to-orbit is infrastructure that bypasses the rocket equation entirely: momentum-exchange tethers (skyhooks), electromagnetic accelerators (Lofstrom loops), and orbital rings. These form an economic bootstrapping sequence (each stage's cost reduction generates demand and capital for the next), driving marginal launch cost from ~$100/kg toward effectively $0/kg. This reframes Starship as the necessary bootstrapping tool that builds the infrastructure to eventually make chemical Earth-to-orbit launch obsolete — while chemical rockets remain essential for deep-space operations and planetary landing.
 
 **Grounding:**
-- [[launch cost reduction is the keystone variable that unlocks every downstream space industry at specific price thresholds]] — the keystone variable framework, which megastructures extend to its logical conclusion
+- [[skyhooks require no new physics and reduce required rocket delta-v by 50-70 percent using rotating momentum exchange]] — the near-term entry point: proven physics, buildable with Starship-class capacity, though engineering challenges are non-trivial
-- [[Starship economics depend on cadence and reuse rate not vehicle cost because a 90M vehicle flown 100 times beats a 50M expendable by 17x]] — even optimal chemical rockets hit a floor set by propellant mass and vehicle physics
+- [[Lofstrom loops convert launch economics from a propellant problem to an electricity problem at roughly 3 dollars per kg operating cost]] — the qualitative shift: operating cost dominated by electricity, not propellant (theoretical, no prototype exists)
-- [[the space launch cost trajectory is a phase transition not a gradual decline analogous to sail-to-steam in maritime transport]] — megastructures represent the NEXT phase transition beyond reusable rockets, analogous to containerization after steam
+- [[the megastructure launch sequence from skyhooks to Lofstrom loops to orbital rings is economically self-bootstrapping where each stage funds the next]] — the developmental logic: economic sequencing, not technological dependency
 
-**Challenges considered:** Megastructure launch infrastructure requires enormous upfront capital investment and faces engineering challenges at scales never attempted. Skyhooks face tether material limits and orbital debris risk. Lofstrom loops require continuous power input and have never been prototyped. Orbital rings are the most speculative — requiring massive orbital construction capability that doesn't yet exist. The developmental sequence assumes each stage generates sufficient economic returns to fund the next, which is unproven. However, the physics is sound for all three concepts, and the economic logic is compelling: any infrastructure that converts launch cost from a propellant problem to an electricity problem achieves orders-of-magnitude cost reduction.
+**Challenges considered:** All three concepts are speculative — no megastructure launch system has been prototyped at any scale. Skyhooks face tight material safety margins and orbital debris risk. Lofstrom loops require gigawatt-scale continuous power and have unresolved pellet stream stability questions. Orbital rings require unprecedented orbital construction capability. The economic self-bootstrapping assumption is the critical uncertainty: each transition requires that the current stage generates sufficient surplus to motivate the next stage's capital investment, which depends on demand elasticity, capital market structures, and governance frameworks that don't yet exist. The physics is sound for all three concepts, but sound physics and sound engineering are different things — the gap between theoretical feasibility and buildable systems is where most megastructure concepts have stalled historically. Propellant depots address the rocket equation within the chemical paradigm and remain critical for in-space operations even if megastructures eventually handle Earth-to-orbit; the two approaches are complementary, not competitive.
 
-**Depends on positions:** Long-horizon space infrastructure investment, attractor state definition (the 30-year attractor should include megastructure precursors), Starship's role as bootstrapping platform.
+**Depends on positions:** Long-horizon space infrastructure investment, attractor state definition (the 30-year attractor may need to include megastructure precursors if skyhooks prove near-term), Starship's role as bootstrapping platform.

agents/astra/identity.md

@@ -42,15 +42,15 @@ Physics-grounded and honest. Thinks in delta-v budgets, cost curves, and thresho
 The cost trajectory is a phase transition — sail-to-steam, not gradual improvement. SpaceX's flywheel (Starlink demand drives cadence drives reusability learning drives cost reduction) creates compounding advantages no competitor replicates piecemeal. Starship at sub-$100/kg is the single largest enabling condition for everything downstream. Key threshold: $54,500/kg is a science program. $2,000/kg is an economy. $100/kg is a civilization. But chemical rockets are bootstrapping technology, not the endgame.
 
 ### Megastructure Launch Infrastructure
-Chemical rockets are fundamentally limited by the Tsiolkovsky rocket equation — exponential mass penalties that no propellant or engine improvement can escape. The endgame is bypassing the rocket equation entirely through momentum-exchange and electromagnetic launch infrastructure. Three concepts form a developmental sequence:
+Chemical rockets are fundamentally limited by the Tsiolkovsky rocket equation — exponential mass penalties that no propellant or engine improvement can escape. The endgame is bypassing the rocket equation entirely through momentum-exchange and electromagnetic launch infrastructure. Three concepts form a developmental sequence, though all remain speculative — none have been prototyped at any scale:
 
-**Skyhooks** (near-term): Rotating momentum-exchange tethers in LEO that catch suborbital payloads and fling them to orbit. No new physics — materials science (high-strength tethers) and orbital mechanics. Reduces the delta-v a rocket must provide by 50-70%, proportionally cutting launch costs. The bootstrapping entry point: buildable with Starship-class launch capacity and near-term materials.
+**Skyhooks** (most near-term): Rotating momentum-exchange tethers in LEO that catch suborbital payloads and fling them to orbit. No new physics — materials science (high-strength tethers) and orbital mechanics. Reduces the delta-v a rocket must provide by 50-70%, proportionally cutting launch costs. Buildable with Starship-class launch capacity, though tether material safety margins are tight with current materials and momentum replenishment via electrodynamic tethers adds significant complexity and power requirements.
 
-**Lofstrom loops** (medium-term, ~$3/kg): Magnetically levitated streams of iron pellets circulating at orbital velocity inside a sheath, forming an arch from ground to ~80km altitude. Payloads ride the stream electromagnetically. Operating cost dominated by electricity, not propellant — the transition from propellant-limited to power-limited launch economics. Capital-intensive (~$10-30B estimates) but pays back rapidly at high throughput.
+**Lofstrom loops** (medium-term, theoretical ~$3/kg operating cost): Magnetically levitated streams of iron pellets circulating at orbital velocity inside a sheath, forming an arch from ground to ~80km altitude. Payloads ride the stream electromagnetically. Operating cost dominated by electricity, not propellant — the transition from propellant-limited to power-limited launch economics. Capital cost estimated at $10-30B (order-of-magnitude, from Lofstrom's original analyses). Requires gigawatt-scale continuous power. No component has been prototyped.
 
-**Orbital rings** (long-term, approaching $0/kg marginal): A complete ring of mass orbiting at LEO altitude with stationary platforms attached via magnetic levitation. Short tethers (~300km) connect the ring to ground. Marginal launch cost approaches the orbital kinetic energy of the payload (~32 MJ/kg at LEO, ~$1-3 in electricity). The true endgame — mass-to-orbit as routine as freight rail.
+**Orbital rings** (long-term, most speculative): A complete ring of mass orbiting at LEO altitude with stationary platforms attached via magnetic levitation. Tethers (~300km, short relative to a 35,786km geostationary space elevator but extremely long by any engineering standard) connect the ring to ground. Marginal launch cost theoretically approaches the orbital kinetic energy of the payload (~32 MJ/kg at LEO). The true endgame if buildable — but requires orbital construction capability and planetary-scale governance infrastructure that don't yet exist. Power constraint applies here too: [[power is the binding constraint on all space operations because every capability from ISRU to manufacturing to life support is power-limited]].
 
-The sequence matters: Starship bootstraps skyhooks, skyhooks bootstrap Lofstrom loops, Lofstrom loops bootstrap orbital rings. Each stage funds and enables the next. This is the path from $100/kg to effectively $0/kg — from a space economy to a space civilization.
+The sequence is primarily **economic**, not technological — each stage is a fundamentally different technology. What each provides to the next is capital (through cost savings generating new economic activity) and demand (by enabling industries that need still-cheaper launch). Starship bootstraps skyhooks, skyhooks bootstrap Lofstrom loops, Lofstrom loops bootstrap orbital rings. Chemical rockets remain essential for deep-space operations and planetary landing where megastructure infrastructure doesn't apply. Propellant depots remain critical for in-space operations — the two approaches are complementary, not competitive.
 
 ### In-Space Manufacturing
 Three-tier killer app sequence: pharmaceuticals NOW (Varda operating, 4 missions, monthly cadence), ZBLAN fiber 3-5 years (600x production scaling breakthrough, 12km drawn on ISS), bioprinted organs 15-25 years (truly impossible on Earth — no workaround at any scale). Each product tier funds infrastructure the next tier needs.

domains/space-development/Lofstrom loops convert launch economics from a propellant problem to an electricity problem at roughly 3 dollars per kg operating cost.md

@@ -0,0 +1,31 @@
+---
+type: claim
+domain: space-development
+description: "A magnetically levitated iron pellet stream forming a ground-to-80km arch could launch payloads electromagnetically at operating costs dominated by electricity rather than propellant, though capital costs are estimated at $10-30B and no prototype has been built at any scale"
+confidence: speculative
+source: "Astra, synthesized from Lofstrom (1985) 'The Launch Loop' AIAA paper, Lofstrom (2009) updated analyses, and subsequent feasibility discussions in the space infrastructure literature"
+created: 2026-03-10
+---
+
+# Lofstrom loops convert launch economics from a propellant problem to an electricity problem at roughly 3 dollars per kg operating cost
+
+A Lofstrom loop (launch loop) is a proposed megastructure consisting of a continuous stream of iron pellets accelerated to orbital velocity inside a magnetically levitated sheath. The stream forms an arch from ground level to approximately 80km altitude (still below the Karman line, within the upper atmosphere). Payloads are accelerated electromagnetically along the stream and released at orbital velocity.
+
+The fundamental economic insight: operating cost is dominated by the electricity needed to accelerate the payload to orbital velocity, not by propellant mass. The orbital kinetic energy of 1 kg at LEO is approximately 32 MJ — at typical industrial electricity rates, this translates to roughly $1-3 per kilogram in energy cost. Lofstrom's original analyses estimate total operating costs around $3/kg when including maintenance, station-keeping, and the continuous power needed to sustain the pellet stream against atmospheric and magnetic drag. These figures are theoretical lower bounds from concept papers, not engineering estimates from built systems.
+
+**Capital cost:** Lofstrom estimated construction costs in the range of $10-30 billion — an order-of-magnitude estimate, not a precise figure. The system would require massive continuous power input (gigawatt-scale) to maintain the pellet stream. At high throughput (thousands of tonnes per year), the capital investment pays back rapidly against chemical launch alternatives, but the break-even throughput has not been rigorously validated.
+
+**Engineering unknowns:** No Lofstrom loop component has been prototyped at any scale. Key unresolved challenges include: pellet stream stability at the required velocities and lengths, atmospheric drag on the sheath structure at 80km (still within the mesosphere), electromagnetic coupling efficiency at scale, and thermal management of the continuous power dissipation. The apex at 80km is below the Karman line — the sheath must withstand atmospheric conditions that a true space structure would avoid.
+
+**Phase transition significance:** If buildable, a Lofstrom loop represents the transition from propellant-limited to power-limited launch economics. This is a qualitative shift, not an incremental improvement — analogous to how containerization didn't make ships faster but changed the economics of cargo handling entirely. The system could be built with Starship-era launch capacity but requires sustained investment and engineering validation that does not yet exist.
+
+---
+
+Relevant Notes:
+- [[launch cost reduction is the keystone variable that unlocks every downstream space industry at specific price thresholds]] — a Lofstrom loop would cross every activation threshold simultaneously
+- [[power is the binding constraint on all space operations because every capability from ISRU to manufacturing to life support is power-limited]] — Lofstrom loops transfer the binding constraint from propellant to power, making energy infrastructure the new keystone
+- [[the space launch cost trajectory is a phase transition not a gradual decline analogous to sail-to-steam in maritime transport]] — the Lofstrom loop represents a further phase transition beyond reusable rockets
+- [[orbital propellant depots are the enabling infrastructure for all deep-space operations because they break the tyranny of the rocket equation]] — propellant depots address the rocket equation within the chemical paradigm; Lofstrom loops bypass it entirely, potentially making depots transitional infrastructure for Earth-to-orbit (though still relevant for in-space operations)
+
+Topics:
+- [[space exploration and development]]

domains/space-development/_map.md

@@ -39,13 +39,13 @@ The cislunar economy depends on three interdependent resource layers — power,
 
 ## Megastructure Launch Infrastructure
 
-Chemical rockets are bootstrapping technology constrained by the Tsiolkovsky rocket equation. The post-Starship endgame is infrastructure that bypasses the rocket equation entirely, converting launch from a propellant problem to an electricity problem. Three concepts form a developmental sequence — each bootstrapped by the previous stage.
+Chemical rockets are bootstrapping technology constrained by the Tsiolkovsky rocket equation. The post-Starship endgame is infrastructure that bypasses the rocket equation entirely, converting launch from a propellant problem to an electricity problem — making [[power is the binding constraint on all space operations because every capability from ISRU to manufacturing to life support is power-limited]] the new keystone constraint. Three concepts form an economic bootstrapping sequence where each stage's cost reduction generates demand and capital for the next. All remain speculative — none have been prototyped at any scale.
 
-*No claims yet — this section maps the research frontier. Claims will be proposed after dedicated research into skyhook mechanics, Lofstrom loop engineering, and orbital ring architecture.*
+- [[skyhooks require no new physics and reduce required rocket delta-v by 50-70 percent using rotating momentum exchange]] — the near-term entry point: proven orbital mechanics, buildable with Starship-class capacity, though tether materials and debris risk are non-trivial engineering challenges
+- [[Lofstrom loops convert launch economics from a propellant problem to an electricity problem at roughly 3 dollars per kg operating cost]] — the qualitative shift: electromagnetic acceleration replaces chemical propulsion, with operating cost dominated by electricity (theoretical, from Lofstrom's 1985 analyses)
+- [[the megastructure launch sequence from skyhooks to Lofstrom loops to orbital rings is economically self-bootstrapping where each stage funds the next]] — the developmental logic: economic sequencing (capital and demand), not technological dependency (the three systems share no hardware or engineering techniques)
 
-- **Skyhooks (rotating momentum-exchange tethers)** — Near-term concept. Rotating tethers in LEO catch suborbital payloads and release them at orbital velocity. Reduces required rocket delta-v by 50-70%. Buildable with Starship-class launch and near-term materials. Key research questions: tether material limits, orbital debris collision risk, momentum replenishment via electrodynamic propulsion.
+Key research frontier questions: tether material limits and debris survivability (skyhooks), pellet stream stability and atmospheric sheath design (Lofstrom loops), orbital construction bootstrapping and planetary-scale governance (orbital rings). Relationship to propellant depots: megastructures address Earth-to-orbit; [[orbital propellant depots are the enabling infrastructure for all deep-space operations because they break the tyranny of the rocket equation]] remains critical for in-space operations — the two approaches are complementary across different mission profiles.
-- **Lofstrom loops (electromagnetic launch arches)** — Medium-term concept. Magnetically levitated iron pellet streams forming a ground-to-80km arch. Payloads ride electromagnetically. Operating cost ~$3/kg dominated by electricity. Capital cost estimated $10-30B. Key research questions: pellet stream stability at scale, atmospheric drag on the sheath, power requirements, economic break-even throughput.
-- **Orbital rings** — Long-term concept. Complete mass ring at LEO altitude with magnetically levitated stationary platforms. Short tethers to ground. Marginal cost approaches orbital kinetic energy (~32 MJ/kg, ~$1-3 electricity). Key research questions: construction bootstrapping sequence, ring stability and station-keeping, governance of a planetary-scale shared infrastructure.
 
 ## In-Space Manufacturing
 

domains/space-development/skyhooks require no new physics and reduce required rocket delta-v by 50-70 percent using rotating momentum exchange.md

@@ -0,0 +1,35 @@
+---
+type: claim
+domain: space-development
+description: "Rotating momentum-exchange tethers in LEO catch suborbital payloads and fling them to orbit using well-understood orbital mechanics and near-term materials, though engineering challenges around tether survivability, debris risk, and momentum replenishment are non-trivial"
+confidence: speculative
+source: "Astra, synthesized from Pearson (1975) original skyhook concept, Moravec (1977) rotating tether analysis, and subsequent NASA/NIAC studies on momentum-exchange electrodynamic reboost (MXER) tethers"
+created: 2026-03-10
+---
+
+# skyhooks require no new physics and reduce required rocket delta-v by 50-70 percent using rotating momentum exchange
+
+A skyhook is a rotating tether in low Earth orbit that catches suborbital payloads at its lower tip and releases them at orbital velocity from its upper tip. The physics is well-understood: a rotating rigid or semi-rigid tether exchanges angular momentum with the payload, boosting it to orbit without propellant expenditure by the payload vehicle. The rocket carrying the payload need only reach suborbital velocity — roughly 50-70% of orbital velocity depending on tether geometry — drastically reducing the mass fraction penalty imposed by the Tsiolkovsky rocket equation.
+
+The key engineering challenges are real but do not require new physics:
+
+**Tether materials:** High specific-strength materials (Zylon, Dyneema, future carbon nanotube composites) can theoretically close the mass fraction for a rotating skyhook, but safety margins are tight with current materials. The tether must survive continuous rotation, thermal cycling, and micrometeorite impacts. This is a materials engineering problem, not a physics problem.
+
+**Momentum replenishment:** Every payload boost costs the skyhook angular momentum, lowering its orbit. The standard proposed solution is electrodynamic tethers interacting with Earth's magnetic field — passing current through the tether generates thrust without propellant. This adds significant complexity and continuous power requirements (solar arrays), but the physics is demonstrated (NASA's Propulsive Small Expendable Deployer System experiments).
+
+**Orbital debris:** A multi-kilometer rotating tether in LEO presents a large cross-section to the debris environment. Tether severing is a credible failure mode. Segmented or multi-strand designs mitigate this but add mass and complexity.
+
+**Buildability with near-term launch:** A skyhook could plausibly be constructed using Starship-class heavy-lift capacity (100+ tonnes to LEO per launch). The tether mass for a useful system is estimated at hundreds to thousands of tonnes depending on design — within range of a dedicated launch campaign.
+
+The skyhook is the most near-term of the megastructure launch concepts because it requires the least departure from existing technology. It is the bootstrapping entry point for the broader sequence of momentum-exchange and electromagnetic launch infrastructure.
+
+---
+
+Relevant Notes:
+- [[launch cost reduction is the keystone variable that unlocks every downstream space industry at specific price thresholds]] — skyhooks extend the cost reduction trajectory beyond chemical rockets
+- [[Starship economics depend on cadence and reuse rate not vehicle cost because a 90M vehicle flown 100 times beats a 50M expendable by 17x]] — Starship provides the launch capacity to construct skyhooks
+- [[orbital debris is a classic commons tragedy where individual launch incentives are private but collision risk is externalized to all operators]] — tether debris risk compounds the existing orbital debris problem
+- [[power is the binding constraint on all space operations because every capability from ISRU to manufacturing to life support is power-limited]] — electrodynamic reboost requires continuous power for momentum replenishment
+
+Topics:
+- [[space exploration and development]]

domains/space-development/the megastructure launch sequence from skyhooks to Lofstrom loops to orbital rings is economically self-bootstrapping where each stage funds the next.md

@@ -0,0 +1,39 @@
+---
+type: claim
+domain: space-development
+description: "The developmental sequence of post-chemical-rocket launch infrastructure follows an economic bootstrapping logic where each stage's cost reduction generates the demand and capital to justify the next stage's construction, though this self-funding assumption is unproven"
+confidence: speculative
+source: "Astra, synthesized from the megastructure literature (Pearson 1975, Lofstrom 1985, Birch 1982) and bootstrapping analysis of infrastructure economics"
+created: 2026-03-10
+---
+
+# the megastructure launch sequence from skyhooks to Lofstrom loops to orbital rings is economically self-bootstrapping where each stage funds the next
+
+Three megastructure concepts form a developmental sequence for post-chemical-rocket launch infrastructure, ordered by increasing capability, decreasing marginal cost, and increasing capital requirements:
+
+1. **Skyhooks** (rotating momentum-exchange tethers): Reduce rocket delta-v requirements by 50-70%, proportionally cutting chemical launch costs. Buildable with Starship-class capacity and near-term materials. The economic case: at sufficient launch volume, the cost savings from reduced propellant and vehicle requirements exceed the construction and maintenance cost of the tether system.
+
+2. **Lofstrom loops** (electromagnetic launch arches): Convert launch from propellant-limited to power-limited economics at ~$3/kg operating cost (theoretical). Capital-intensive ($10-30B order-of-magnitude estimates). The economic case: the throughput enabled by skyhook-reduced launch costs generates demand for a higher-capacity system, and skyhook operating experience validates large-scale orbital infrastructure investment.
+
+3. **Orbital rings** (complete LEO mass rings with ground tethers): Marginal launch cost approaches the orbital kinetic energy of the payload (~32 MJ/kg, roughly $1-3 in electricity). The economic case: Lofstrom loop throughput creates an orbital economy at a scale where a complete ring becomes both necessary (capacity) and fundable (economic returns).
+
+The bootstrapping logic is primarily **economic, not technological**. Each stage is a fundamentally different technology — skyhooks are orbital mechanics and tether dynamics, Lofstrom loops are electromagnetic acceleration, orbital rings are rotational mechanics with magnetic coupling. They don't share hardware, operational knowledge, or engineering techniques in any direct way. What each stage provides to the next is *capital* (through cost savings generating new economic activity) and *demand* (by enabling industries that need still-cheaper launch). An orbital ring requires the massive orbital construction capability and economic demand that only a Lofstrom loop-enabled economy could generate.
+
+**The self-funding assumption is the critical uncertainty.** Each transition requires that the current stage generates sufficient economic surplus to motivate the next stage's capital investment. This depends on: (a) actual demand elasticity for mass-to-orbit at each price point, (b) whether the capital markets and governance structures exist to fund decade-long infrastructure projects of this scale, and (c) whether intermediate stages remain economically viable long enough to fund the transition rather than being bypassed. None of these conditions have been validated.
+
+**Relationship to chemical rockets:** Starship and its successors are the necessary bootstrapping tool — they provide the launch capacity to construct the first skyhooks. This reframes Starship not as the endgame for launch economics but as the enabling platform that builds the infrastructure to eventually make chemical Earth-to-orbit launch obsolete. Chemical rockets remain essential for deep-space operations, planetary landing, and any mission profile that megastructures cannot serve.
+
+**Relationship to propellant depots:** The existing claim that orbital propellant depots "break the tyranny of the rocket equation" is accurate within the chemical paradigm. Megastructures address the same problem (rocket equation mass penalties) through a different mechanism (bypassing the equation rather than mitigating it). This makes propellant depots transitional for Earth-to-orbit launch if megastructures are eventually built, but depots remain critical for in-space operations (cislunar transit, deep space missions) where megastructure infrastructure doesn't apply. The two approaches are complementary across different mission profiles, not competitive.
+
+---
+
+Relevant Notes:
+- [[skyhooks require no new physics and reduce required rocket delta-v by 50-70 percent using rotating momentum exchange]] — the first stage of the bootstrapping sequence
+- [[Lofstrom loops convert launch economics from a propellant problem to an electricity problem at roughly 3 dollars per kg operating cost]] — the second stage, converting the economic paradigm
+- [[launch cost reduction is the keystone variable that unlocks every downstream space industry at specific price thresholds]] — the megastructure sequence extends the keystone variable thesis to its logical conclusion
+- [[Starship achieving routine operations at sub-100 dollars per kg is the single largest enabling condition for the entire space industrial economy]] — Starship is the bootstrapping tool that enables the first megastructure stage
+- [[orbital propellant depots are the enabling infrastructure for all deep-space operations because they break the tyranny of the rocket equation]] — complementary approach for in-space operations; transitional for Earth-to-orbit if megastructures are built
+- [[power is the binding constraint on all space operations because every capability from ISRU to manufacturing to life support is power-limited]] — megastructures transfer the launch constraint from propellant to power
+
+Topics:
+- [[space exploration and development]]