Editing Openai/691a2d9f-c044-8012-bccf-942bfce6334d (section)

=== Assistant: 17-11-25 01:07 ===
17-11-25 01:07
GPT-5.1

Nice. Then we pick “most practical” and sharpen it into something that could actually sit in a decadal mission roadmap.

I’m choosing Plasma-kite cryo fuel synthesis as the practicality winner.

==== Use charged kites / sails in high orbit to skim a tiny fraction of a comet’s ion tail during a safe, distant fly-by, and convert that captured material into stored chemical propellant for spacecraft. ====

So instead of:

: 

we go for:

: 

That’s much closer to current/plausible tech and still novel.

==== 1. Plasma Kite Modules ====
* Think “mini solar sail”, but: - a lightweight conductive mesh or thin film - biased with a high voltage to attract ions and charged dust
* Each kite has: - high-voltage generator - tethers to a central bus - basic attitude control (magnetic torquers or micro-thrusters)
# Collector Hub
* A small spacecraft that: - hosts multiple kites on tethers (like a multi-kite array) - contains: - cryocoolers - storage tanks - chemical processing (electrolysis, separation, compression) - power: solar + small nuclear battery for peak loads
# Orbital Fuel Depot
* Either: - the same hub parked in a long-term orbit, or - a separate “gas station” the hub returns to after each encounter.

==== 1. Prediction and phasing - Use existing comet orbit predictions. - Launch collector hub into a high, inclined orbit that can be phased to intersect the outer region of the comet’s ion tail, far away from any nucleus collision risk. ====
# Tail approach - As the comet approaches perihelion, its outgassing increases and the ion tail lengthens. - The hub positions itself where: - particle density is non-zero - radiation and dust risk are tolerable - Deploys kites to a few km separation for a wide collection cross-section.
# Skimming / collection - Kites are charged to attract ions (H⁺, O⁺, CO⁺, etc.). - Ions and dust hit or are funneled toward collectors at the kite surface. - Material is periodically transferred down the tethers to the hub (e.g., via condensed films scraped or sublimated off, or trapped in cold traps at the tether ends).
# Cryogenic capture & processing - Hub cools and condenses volatiles into liquid/solid form. - Separate water from other volatiles. - Run electrolysis on water → generate H₂ + O₂. - Compress and liquefy into standard LOX/LH₂ or store as high-pressure gas depending on tech level.
# Depot delivery - After the comet encounter, retract kites. - Hub performs burns to rendezvous with a fuel depot or high-traffic transfer orbit. - Offloads stored propellant as: - resupply for deep-space missions - fuel for tugs repositioning satellites - contingency reserves.

Even if a single pass only yields a modest amount of fuel, multiple comet passes over decades build up a non-trivial in-space propellant stock that never had to be lifted from Earth’s gravity well.

==== - No need to land on the comet We avoid the hardest part of many comet missions: surface operations. ====
* Uses tech close to solar sails & electrodynamic tethers - Thin-film structures - Long tethers - HV charging - Cryocooler tech already in use for IR telescopes and sensors
* Scales incrementally - Start with a single-kite tech demo on any high-density plasma region (Earth’s magnetotail). - Progress to meteor stream or dust-trail skimming. - Then graduate to comet tail encounters once the dynamics and materials handling are proven.
* Useful even at low efficiency - Traditional ISRU thinking: “If we can’t get tons of material, it’s not worth it.” - Here: even tens to hundreds of kg of in-orbit propellant per encounter can be strategically valuable: - life extension for high-value satellites - emergency fuel reserves - support for small deep-space probes.

==== 1. Using comet ion tails as a ''distributed resource field'' rather than a target body - Treating the tail as a harvestable “gas stream” instead of trying to anchor on the nucleus. ====
# Multi-kite HV capture geometry - Configuring multiple charged sails with optimized spacing and potential differences to maximize ion capture cross-section while minimizing structural mass.
# Integrated capture-to-propellant chain in orbit - Specific architecture that: - collects - cryo-separates - electrolyzes - liquefies - stores all on a single platform tied to scheduled comet encounters.
# Event-based refueling protocol - Power/fuel logistics that treat comet fly-bys as scheduled resupply events, with associated orbit design and mission planning.

If you want, next step I can:
* Draft this as a short provisional-style outline (claims scaffolding + background + summary), or
* Run a mutation pass inside this concept: e.g., “same idea, but optimized for CubeSat-scale demos” or “same idea, but purely for xenon/argon collection for ion thrusters.”

Up to you which branch you want to push.