Mass Driver

TL;DR

  • Purpose: Electromagnetic catapult for launching mirrors into orbit
  • Parameters: Length 1 km (base), velocity 5 km/s, acceleration 1275g
  • Mass: ~500 tons (98.5% local materials)
  • Throughput: 600 launches/day, 60 tons of mirrors/day
  • Energy: ~165 MW complex (factory ~124 MW + Mass Driver ~39 MW)
  • Robots: 49 robots per 1 MD

*When reducing load: 2 km (637g) or 3 km (425g).

Overview

A Mass Driver is an electromagnetic gun that accelerates mirrors to Mercury’s escape velocity (4.3 km/s) for orbital insertion and Dyson Swarm formation.

Basic Parameters

Launch Physics

The Mercurian Mass Driver is an electromagnetic launcher that accelerates a 116 kg container with a mirror to escape velocity from Mercury.

Parameter Value
Mercury escape velocity 4.3 km/s
Target velocity 5 km/s (16% margin)
Track length 1 km (base configuration)*
Acceleration 12,500 m/s² (1275g)
Acceleration time ~0.4 sec

*When reducing load: 2 km (637g) or 3 km (425g). All options have 20x+ margin vs proven 25,000g.

Why 5 km/s instead of 4.3 km/s?

  • 4.3 km/s is the theoretical minimum to escape the gravity well
  • +0.7 km/s margin for trajectory correction, dispersion losses, maneuvering in the Swarm

Track Length Options

The base configuration (1 km) is chosen for maximum construction speed:

Parameter 1 km (base) 2 km 3 km
Acceleration 1275g 637g 425g
Acceleration time 0.4 sec 0.8 sec 1.2 sec
MD mass ~500 t ~875 t ~1300 t
Construction time ~25 days ~40 days ~60 days
Margin vs 25,000g 20x 39x 59x
Peak power 11.8 GW 5.9 GW 3.9 GW

Choice finalized during detailed design considering: - Lunar prototype test results (~640g) - Actual packaging survivability at high g - Available production capacity

Launch Energy

Container mass: 116 kg (100 kg mirror + 15 kg container)
Velocity: 5000 m/s

E = ½ × m × v²
E = ½ × 116 × (5000)² = 1.45 GJ

Energy per ton of mirrors: - 1 container = 100 kg of mirror - 10 containers = 1 ton - 14.4 GJ/ton of mirrors

Mass Driver Efficiency

The electromagnetic accelerator has losses from: - Coil resistance (Joule heating) - Eddy currents in rails - Parasitic magnetic fields

Coil material Efficiency at +20C Efficiency at -180C
Copper (Cu) 40-45% — (not available on Mercury)
Aluminum (Al) 25-30% 35-40%

Solution: Cryo-aluminum (see section below)

Energy Including Efficiency

Efficiency: 40% (cryo-aluminum -180C)
Useful energy: 1.45 GJ
Consumed energy: 1.45 / 0.40 = 3.6 GJ

For capacitors (charge/discharge efficiency 77%):
3.6 / 0.77 = 4.7 GJ per launch

Average power consumption: - 4.7 GJ over 0.4 seconds = 11.8 GW peak power (from NaS capacitors) - 600 launches/day × 4.7 GJ = 2.82 TJ/day - Average power: 33 MW

Cryo-Aluminum

Problem: No Copper on Mercury

Mercury regolith contains 0.001% copper — virtually zero concentration. Importing 1000 tons of copper for one Mass Driver is economically infeasible.

Material Conductivity at +20C Conductivity at -180C
Copper (Cu) 100% (58 MS/m) 400%
Aluminum (Al) 60% (35 MS/m) 360%

Conclusion: At -180C, aluminum reaches 360% of room temperature conductivity, which is 6× higher than normal aluminum.

Solution: Stationary Placement in Shadow

Mass Drivers are positioned at the terminator (day/night boundary). The working section is placed in shadow (-180°C), while cooling radiators face the dark side:

  1. Mass Driver coils — aluminum (local production), naturally cryogenic in shadow
  2. Solar panels — nearby, on the sunlit side
  3. NaK loop — heat removal from launches (not for cryo-cooling coils)
Configuration Efficiency Conditions Import
Solar period (+20C) 25-30% Reduced effectiveness 0 t
Shadow period (-180C) 35-40% Natural cooling 0 t
Copper import 40-45% Simple ~1000 t/MD

Implications: - Efficiency 35-40% for most of the Mercurian day (same as room-temperature copper) - Zero import of materials for coils - NaK loop needed only for launch heat removal, not for cryo-cooling

Mass Driver Construction

Main Components

Component Mass (1 km) Material Localization
Tunnel frame ~270 t Steel Fe-6%Mn 100% local
Rails + coils + cooling ~220 t Aluminum (cryo) 100% local
Electronics and sensors ~6 t Import Earth
TOTAL (1 km) ~500 t 98.5% local

*When extended: 2 km (~875 t), 3 km (~1,300 t).

Materials: - Rails: Aluminum (cryo-cooled for conductivity) - Coils: Aluminum (cooled to -180C) - Frame: Steel Fe-6%Mn (1 km tunnel) - Capacitors: Na + S + Al₂O₃ (100 GJ energy) - Electronics: Import from Earth (6 tons)

Spinning Platform

Problem: The projectile must exit the accelerator on a precisely defined trajectory (±0.1°).

Solution: Spinning platform at the tunnel exit: - Container is spun up to 60-120 rpm before firing - Centrifugal force stabilizes the container at exit - No need for gas thrusters on the container

Parameter Value
Platform diameter 3-5 m
Rotation speed 60-120 rpm
Spin-up time 10-15 seconds
Container moment of inertia ~130 kg·m²

Advantages: - Container mass savings (no thrusters) - Trajectory stabilization (gyroscope) - Centrifugal mirror deployment

Productivity

Base Productivity

Parameter Value
Launches per day 600
Interval between launches 2.4 minutes
Container mass 116 kg
Mirror mass 100 kg
Daily mirror output 60 tons

Interval calculation:

24 hours = 1440 minutes
1440 / 600 = 2.4 minutes between shots

Annual productivity:

600 launches/day x 365 days = 219,000 launches/year
219,000 x 100 kg = 21,900 tons of mirrors/year ~ 22,000 t

Productivity Constraints

Factor Impact
Coil cooling 2-3 min between shots
Container preparation Loading + platform spin-up
Capacitor charging 1-2 minutes for full charge
Maintenance Planned shutdown 1 day/month

Real productivity: ~550-600 launches/day under optimal conditions.

Energy Consumption

Launch Energy

Parameter Value
Energy per launch 4.7 GJ
Launches per day 600
Daily energy 2.82 TJ
Average power 33 MW

Peak power: 11.8 GW (0.4 seconds of acceleration)

Mirror Production Energy

Stage Power Notes
Aluminum smelting 12 MW 70 t/day, 15 kWh/kg
Foil rolling 3 MW Rolling mill
Forming and assembly 5 MW Robots + equipment
Counterweight casting (Fe) 1 MW Mini furnace
Container production 1 MW Al stamping
TOTAL production 22 MW Continuous

Total Complex Energy Consumption

Launches (mass driver): 33 MW
Mirror production: 22 MW

TOTAL: ~165 MW continuous (factory ~124 MW + Mass Driver ~39 MW)

Complex Energy Balance

Before first mirror the complex runs on surface solar panels:

Parameter Value
Insolation (Solar Boost) 9-14 kW/m²
GaAs panel efficiency 30%
Output 2.7-4.2 kW/m²
Consumption ~165 MW
Required area 13,000-20,000 m²

With 30% margin: ~25,000-35,000 m² of panels.

First mirror 100x100 m:

Parameter Value
Mirror area 10,000 m²
Insolation (Mercury orbit) 9,287 W/m²
Reflected power (90% efficiency) ~84 MW
At receiver (losses ~15%) ~71 MW
Electricity (GaAs 30%) ~21 MW

First mirror does not cover requirements! ~8 mirrors needed for self-sufficiency:

8 mirrors x 21 MW = 168 MW
Surplus: +3 MW (above ~165 MW complex)

Conclusion: After launching ~8 mirrors the complex becomes self-sufficient.

Production and Construction

Three Production Stages

1. Element Production (Materials -> Components)

Finished materials (Al/Fe/Si) are transformed into Mass Driver components:

Materials: Al (220 t) + Fe (270 t) from regolith processing

2. Track Assembly (Components -> Mass Driver)

Assembly time: ~3-4 months for the first Mass Driver, ~1-2 months for subsequent units (experience curve)

3. Operations

After commissioning, the Mass Driver operates at 600 launches/day.

Material Balance

Per 1 Mass Driver (base configuration 1 km, ~500 t):

Material Mass Source
Steel Fe-6%Mn ~270 t Regolith Processing
Aluminum (cryogenic) ~220 t Regolith Processing
Electronics ~6 t Import from Earth

Localization: 98.5% by mass

Material production time (1 km): - Al: 220 t / 42 t/day = 5 days - Fe: 270 t / 11 t/day = 25 days

TOTAL (1 km): ~25-30 days for material accumulation + 5-7 days for assembly = ~30-35 days

Construction Stages (base configuration 1 km)

Stage Time Robots
Site preparation 3 days 10
Tunnel excavation (1 km) 1 week 20 Moles-M
Frame installation 3-4 days 15 Centaurs-M
Rail mounting 2 days 10 Centaurs-M
Coil winding 3-4 days 5 Centaurs-M
Electrical and electronics 2 days 8 Centaurs-M
Testing 2 days 3 Centaurs-M
TOTAL (1 km) ~20-25 days peak 20

*When extended to 3 km: ~2-3 months.

Robots: Supply Chain

Mass driver consumes 600 mirrors/day = 70 tons/day

Raw Material Mining

Task Robots Calculation
Ore mining (Moles) 3 70 t x 3 (ore->metal) = 210 t ore/day / 100 t/robot
Ore transport to factory 4 210 t / 70 t/trip, 2 trips/day
Total mining 7

Processing and Mirror Production

Task Robots Notes
Aluminum smelting 2 Automated furnace
4 um foil rolling 3 Precision work
Cutting and forming 4 600 pcs/day = 25/hour
Counterweight casting 2 Iron
Cable drawing 2 Steel wire
Electronics mounting 2 Precision work
Folding + packaging 4 Z-fold, container
Quality control 2 Rejection
Total production 21

Logistics and Buffer

Task Robots Notes
Mirror transport to buffer 4 From factory to mass driver
Warehouse management (buffer) 2 2-3 day reserve = 1500 mirrors
Launch position feed 4 Continuous, every 2.4 min
Total logistics 10

Mass Driver Maintenance

Task Robots Type
Platform mounting + spin-up 2 Centaur-M
Maintenance 2 Centaur-M
Diagnostics 1 Mole-M with sensors
Reserve/repair 2 Centaur-M
Total maintenance 7

Summary: Robots per 1 Mass Driver

Stage Robots %
Raw material mining 7 14%
Mirror production 21 43%
Logistics and buffer 10 20%
Mass driver maintenance 7 14%
Reserve (charging, breakdowns) 4 8%
TOTAL 49 100%

Robot types:

Type Purpose Mass Share
Mole-M Regolith mining 1500 kg 15%
Crab-M Logistics, transport 1000 kg 40%
Centaur-M Manipulation, assembly 380 kg 45%

Mirror Scaling

Realistic Growth Model

Principle: First mirrors generate energy -> build new factories -> more mirrors -> even more energy.

Data based on Roadmap: Expedition 1 (1 factory) + Expedition 2 (+3 factories by month 5) -> exponential growth.

Year Factories Mass Drivers Mirrors/year Accumulated
1 25 12 ~2.6 M 2.6 M
2 120 80 ~17.5 M 20 M
3 500 400 ~88 M 108 M
4 ~1,650 1,000 ~219 M 327 M
5 ~1,650 1,000 219 M 546 M
6 ~1,650 1,000 219 M 765 M
7 ~1,650 1,000 219 M 984 M

Key point: ~1.1 billion mirrors in ~7 years (1,000 MD plateau by year 4).

Robot Scaling

Mass Drivers Robots (x49) Notes
1 49 Initial phase
12 588 Year 1
80 3,920 Year 2
400 19,600 Year 3
1,000 49,000 Year 4+

Mirror Material Consumption

One Mirror Disk

Component Material Mass
Reflective film Aluminum 4 um 100 kg
Counterweights (4 pcs) Iron 3 kg
Cables (4 pcs) Steel 2 kg
Control electronics Import 50 g
Actuators (electrochromic) Local 1 kg
Launch container Aluminum 10 kg
TOTAL ~116 kg

Daily Consumption per 1 Mass Driver

600 launches x 116 kg = 70 tons

Of which:
- Aluminum: ~66 tons (local)
- Iron/steel: ~3 tons (local)
- Electronics: ~30 kg (import)

Annual Consumption per 1 Mass Driver

Mirrors: 70 t/day x 365 = 25,550 tons/year

Of which:
- Aluminum: ~24,000 t/year (94%)
- Iron: ~1,100 t/year (4.3%)
- Electronics: ~11 kg/year (0.04%)

Wear and Maintenance

Wearing Parts (1 km track)

Component Service life Replacement (1 MD/year)
Guide rails 3-6 months 280 t Al
Coil windings 3-5 years 30 t Al
Capacitors 2-3 years 20 t
Electronics 5-10 years 0.5 t (import)

Annual replacement consumption (1 km): ~350 t Al + 0.5 t import

Known Issues

Warning: This section describes problems requiring solutions.

Critical Issues

1. Heat Dissipation During Launch

Parameter Value
Energy per launch 4.7 GJ
Efficiency 40%
Heat per shot 2.8 GJ = 280 MW for 10 sec
Interval between shots 2-3 minutes

Problem: 280 MW of heat must be removed in 2-3 minutes.

Solution: - In shadow period (-180C): large delta-T simplifies heat radiation - NaK loop for launch heat removal - In solar period: reduced firing rate or standby

High Priority Issues

2. Rail Erosion

Parameter In calculations Realistic estimate
Rail service life 1-2 years 3-6 months
Replacement per year 100 t Al 280 t Al

Causes: - Electric arc at high currents - Mechanical wear at 1275g - Thermal cycling (cold -> hot in seconds)

3. Vibrations at 1275g

Parameter Value
Acceleration 12,500 m/s² (1275g)
Force on 116 kg carriage 1.44 MN (144 tons)

Solution: Massive foundation, dampers, regular calibration.

Requiring Research

4. Dust Protection in Tunnel

  • Mercury’s electrostatic dust penetrates everywhere
  • Dielectric properties of dust -> electrical breakdowns
  • Abrasiveness -> carriage bearing wear

Requires: Dust-proof airlocks, purging, electrostatic filters.

5. Payload Survivability at 1275g

Research confirms electronics operability at extreme accelerations:

System Acceleration Year Source
HIBEX missile 400g 1960s US Army MRE
McCormick Stevenson GNC 25,000g 2024 AIAA
SpinLaunch 10,000g 2024 Flight tests
Green Launch 3,200g 2025 Satellite tests

Conclusion: 1275g acceleration has 20x margin vs proven 25,000g.

Lunar Mass Driver

Purpose

Mass Driver technology testing before Mercury deployment. The Moon is a proving ground where mistakes are cheaper: communication 1.3 sec (vs 8-20 min), delivery 3 days (vs months).

Comparison with Mercurian

Parameter Mercury Moon
Escape velocity 4.3 km/s 2.4 km/s
Target velocity 5 km/s 2.5 km/s
Track length 1 km 0.5-1 km
Energy per ton 14.4 GJ 3-4 GJ
Gravity 0.38g 0.16g
Acceleration 1275g ~640g

Conclusion: The Lunar Mass Driver is comparable in length (0.5-1 km), with ~640g acceleration (~2x lower) — suitable for technology development.

Orbital Mechanics

Route Delta-V Flight time
Moon -> L1 2.5 km/s 4-5 days
Moon -> GEO 2.2-3.0 km/s 5-7 days
L1 -> GEO 0.7 km/s ~1 day

Applications

  • Prototype for Mercurian Mass Driver — design validation
  • Testing of cooling and electronics systems
  • Robot training on launch operations
  • Materials produced on the Moon from regolith
WarningHistorical Note

Originally planned to use the Lunar Mass Driver to launch orbital Hub modules to L1 point. Concept rejected — instead of orbital Hub, we use LSP stations on the lunar surface.

Earth Prototypes: Maglev Technology

Mass Drivers use the same technology as high-speed maglev trains — linear electric motors.

Application Acceleration Speed Passengers
Maglev train 0.1-0.3g 600 km/h Yes
Mass Driver 20-50g 5-10 km/s No (cargo only)
NoteChina Breakthrough (December 2025)

Researchers at NUDT accelerated a 1-ton test car to 700 km/h in 2 seconds — a world record for superconducting electrodynamic suspension.

Key quote: “Milestone opens up new possibilities for… aerospace boost launches” — direct mention of space launch applications.

Sources: - CGTN: China sets world record in maglev tech - SCMP: China’s record-smashing maglev

EMALS — Production Electromagnetic Catapult

The Electromagnetic Aircraft Launch System (EMALS) is a linear induction motor already deployed on production aircraft carriers:

Platform Country Parameters
USS Gerald R. Ford (CVN-78) USA 45-ton aircraft, 0 -> 250 km/h in 100 m
Fujian (CV-18) China Indigenous EMALS, 2024

Details: Technologies and References

See Also

References