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        Plasmas as Multiscale

     Plasmas encompass an astronomically
      large range of scales in length, density and   
      temperature (equivalent to thermal energy).   
     The well-known length scale change in going   
      from the microscopic to cosmic scale, as   
      presented by Charles and Ray  Eames, is
      even more dramatically illustrated
by plasmas,
      which encompass an enormous   range of scales
      in density, temperature   (energy), field magnitude
     and length!

NASA

                 Plasma Experiments - Space to Laboratory
Mesoscopic or mesoscale processes are encountered from condensed matter physics to space plasmas, from less than 10-7 to more than 10+7 meters. The relationship of microscopic to macroscopic phenomena has long been a central theme of statistical physics and other fields. However, recognition of the natural emergence of distinct mesoscale processes and structures, especially clear and prominent in various plasma systems, is a new development.
                          
                                     Plasma Scale Variations

Scale Lengths (cm): 10-10 to 10+25

Mass density (grams/cm3): 10-27 to 10+10
[highest density, shortest scale comes from quark-gluon plasma where electromagnetic force is replaced by the short-range, strong force]

Number density: from less than 10-4 to more than 10+30 cm3

Temperature (thermal energy): from near absolute zero (crystalline states in recent non-neutral laboratory plasmas) to more than 100 keV

Magnetic fields: less than 10-6 to more than 10+14 gauss

Plasma lifetimes: characteristic time scales from picoseconds to infinity

Tables of Laboratory, Space and Astrophysical Parameters 
second table adapted from T. Eastman, IEEE Trans. Plasma Science, 18, 18-25, 1990. 
 
Space Plasma
Size (km)
Laboratory
Size (mm)
 
spacecraft
0.001
0.001
Microscale
screening
1
sensor
1
 
gyrations
100
Mesoscale
filaments
1000
filaments
10
 
plasma sheet
10,000
100
Macroscale
magnetosphere
100,000
chamber
1000
 
heliosphere
1,000,000,000
   

Parameter
Ionospheres and Magnetospheres
Interstellar Regions
Stellar Winds and Stellar Spheres
Stars
plasma density (cm-3)
<0.0001 -100,000
0.001 - 10
0.001 - 1000
log 7 - 30
neutral density (cm-3)
0 - 100,000
0.01 - 1
0.1 - 100
0
thermal energy (eV)
<1 - 10,000
1 - 10,000
1 - 100
0.5 - 2000
bulk speed (km/s)
0 - 1500
1 - 30
10 - 1000
0 - 500
magnetic field (nanotessla)
1 - 10,000
<0.1 - 1
0.01 - 50
log 5 - 9
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