This document proposes a concept called Mini-Magnetospheric Plasma Propulsion (M2P2) that would create a magnetic bubble around a spacecraft that is pushed by the solar wind, providing thrust with low power. It has the potential to transport payloads faster and farther than conventional propulsion. The document outlines the science behind M2P2, describes prototypes that generated strong magnetic fields and plasma, and demonstrated inflation and solar wind deflection. Future work includes verifying thrust efficiency and testing different propellants for possible applications like missions to Mars.

1. Mini-Magnetospheric Plasma Propulsion
(M2P2)
R. M. Winglee, T. Ziemba, J. Slough, P. Euripides,
Univ. of Washington
D. Gallagher, P. Craven, NASA, MSFC
W. Tomlinson, J. Cravens, J. Burch, SwRI
Create a magnetic bubble around and attached to a spacecraft
that will be pushed by the solar wind to produce a substantial
enhancement in the thrust on the spacecraft for a given power

2. The Solar System : A Large Unexplored Region
Voyager 1:
Launched 1977

3. The Need for Advanced Propulsion Systems
Advanced
Electrical
(MPD)
Ion Engines
(Deep Space 1)
M2P2
Specific Impulse (sec)
Thrust (N)
Chemical Propellants
10
1
.1
.01
100 1,000 10,000 100,000

4. The Dynamic
Sun:
Visible UV soft X-Rays
Electrical Storms raising the solar corona
(solar atmosphere to 2 million degrees)

5. Expanding Magnetic Flare Loops seen by Yohkoh

6. The Solar Wind
•Charged Particles: Ions
and electrons
•300-800 km/s
•Tenuous being only
about 6 particles
per cubic cm at
Earth

7. Magnetosphere: Magnetic field, usually attached to
a planet or moon, that is able to deflect the
charged particles of the solar wind

8. Example of Solar Wind Ions
interacting with a magnetosphere

9. Example of Solar Wind Ions
interacting with a magnetosphere

10. Example of Solar Wind Ions
interacting with a magnetosphere

11. Example of Solar Wind Ions
interacting with a magnetosphere

12. Example of Solar Wind Ions
interacting with a magnetosphere

13. Example of Solar Wind Ions
interacting with a magnetosphere

14. Example of Solar Wind Ions
interacting with a magnetosphere

15. M2P2
• Seeks to create a magnetosphere around the spacecraft
• Enhanced the size of the magnetosphere by the injection of low energy plasma
• Size needs to be about 20-30 km radius
•Advantage is that the inflation is done fully electromagnetically, and
deployment of large scale structures in space

17. Initial Magnetic Field
Terrestrial
Field Lines
Magnetic
Field
Lines

18. Expanding Magnetic Field
Terrestrial
Field Lines
Magnetic
Field
Lines

19. Expanding Magnetic Field
Terrestrial
Field Lines
Magnetic
Field
Lines

20. Terrestrial
Field Lines
Expanding Magnetic Field
Magnetic
Field
Lines

21. M2P2 Milestones:
Prove Feasibility through Computer Simulations
Generation of High Density, Strongly Magnetized Plasma
1011 cm-3 plasma density
300 G magnetic field
1 kW of Power
~ 0.25 to 1 kg/day fuel consumption
Demonstrate Inflation of Magnetic Field
Demonstrate Deflection of an external Plasma Wind
Test Performance of Different Propellants
Measure Thrust and verify Efficiency

22. M2P2 Capabilities
Mini-Magnetosphere (Single Unit) : 20-30 km Radius
Inflation is Purely Electromagnetic
No Large Mechanical Struts have to be deployed
Intercept
~ 1-3 N of Solar Wind Force
~ 0.6 MW of Solar Wind Energy using only ~ 1kW
Scientific Payload of 100 to 200 kg would attain
50- 80 km/s in 3 month acceleration period
Economies of Scale for Multiple Units

23. Experimental Arrangement
400 Liter Vacuum
Chamber
Propellant Bottle
RF Amplifier
Power Supply

24. Mini-Magnetospheric Plasma Propulsion:
Prototype Development and Performance
Electronics Box Gas Feed Support Strut
• Prototype Specifications
– 11 cm radius magnet, 300-1000 G
– Antenna, small (1.5 cm radius) and large
( 2.5 cm radius), ~ 1kW
• Prototype Performance
– Sustained densities of 1013 cm-3
– Temperatures of 4 – 12 eV
– Small Antenna: 0.4 kg/day (5.4 mg/s) @
25% gas efficiency, for 3.3 amps of
plasma and 4 mN
– Large Antenna: 0.8 kg/day (11 mg/s)
@50% gas efficiency, for 12 amps and
16 mN
•Variety of Propellants Possible
–Argon or Helium (for lab use)
–Nitrogen/Hydrogen
–Water – refueling in space
–Other light weigh fuels : CH4, NH3
CO2,
RF Antenna
Magnetic Field Coil

25. Examples of
Plasma
Inflation

27. NASA/MSFC
Test Area 300
Vacuum Chamber
32 ft high by 18 ft
Objectives:
• Demonstrate Magnetospheric
Inflation
•Demonstrate Magnetospheric
Plasma Deflection

28. Demonstration of
Plasma Expansion of a
Mini-Magnetosphere:
•Large Chamber Tests at MSFC
Helium plasma @ 350 G
–Vacuum field solution shows no
closed field lines within ~ 3ft
–Plasma emissions initially seen to
closely match the vacuum
field solution
–Expansion seen as plasma β
approaches unity.
–Expansion out to at least 30 times
the magnet radius
demonstrated.
–Main limitation due to
recombination with chamber
neutrals

29. M2P2: MSFC Operation

30. Demonstration of
Plasma Deflection by a
Mini-Magnetosphere:
M2P2 vs SEPAC
•SEPAC (right hand side)
– 4 Amp Xenon ion source
– 800 W @ 1 eV
•M2P2 (left hand side)
– ~ 4 Amps of Argon @ 400 W
– the two sources separated by about
14 ft (only 6ft field of view
around M2P2 shown in figures)
•Deflection
–Permanent barrier (magnetopause)
seen better the two plasmas
–Barrier moves to the right as the
magnetosphere is inflated
–Barrier moves to right with increase
magnetic field
(a) 400 G (Shot P)
(b) 800 G (Shot Q)

31. M2P2 vs SEPAC

32. Mission Designs:
• Mars Return (1.8 yrs)
• Jupiter Orbital (1.3yrs)
• Saturn/Titan (5.6 yrs)
• Pluto (6.2 yrs)
• Heliopause (10 yrs)

33. Example M2P2 Mission
250 Days to Mars Earth Orbit
Mars Orbit
M2P2 On
Coast

34. 250 Days to Mars
130 Days on Surface
Earth Orbit
Mars Orbit
M2P2 On
Coast
Example M2P2 Mission

35. 250 Days to Mars
130 Days on Surface
290 Day Return
Earth Orbit
Mars Orbit
M2P2 On
Coast
Example M2P2 Mission

36. 250 Days to Mars
130 Days on Surface
290 Day Return
Total: 1.8 Years
Earth Orbit
Mars Orbit
M2P2 On
Coast
Example M2P2 Mission

37. Concept
Mar.,99
1st Prototype
Dec.,99
NIAC Timeline
Large Chamber
Phase II
Testing
Aug.,00
Verification
of concept
Feb.,01 Efficiency,
Thrust
Phase I Present