Differences between revisions 3 and 10 (spanning 7 versions)

The Plasmasphere

Most of the mass of particles in server sky orbits is cold (<1eV) plasma, in the upper fringes of the atmosphere. The total mass of these particles is small. This plot shows density versus distance.

This plot is modified from http://plasmasphere.nasa.gov/media/meridianswing.html

orbit	Radius	L_min	L_max	Dens_min	Dens_max	Volume	Mass
m288	12789 km	1.93	2.14	4500/cm³	7000/cm³	1.8e12 km³	17000 kg
m360	14441 km	2.19	2.42	2500/cm³	4000/cm³	2.6e12 km³	14000 kg
m480	16756 km	2.55	2.79	1200/cm³	2500/cm³	3.5e12 km³	11000 kg
Earth						1.1e12 km³	6e24 kg
Troposphere						8e9 km³	5e18 kg

A few thousand tons of thinsats will vastly increase the number of coulomb scattering centers.

MoreLater

The magnetosphere

The dipole field at the equator is 31000nT. A geomagnetic storm changes this by depositing a westward ring of electric current, which induces a negative change in the field:

-30nT to -50nT	weak storm
-50nT to -100nT	moderate storm
> -100nT	intense
> -300nT	"a few times per solar cycle

Shrivjer and Siscoe "Heliophysics" pp265 Cambridge 2010
Also see www.nerc.com/files/GMD_Workshop_Report_April_2011.pdf (chair Don Watkins BPA)

-  ⇤ ← Revision 3 as of 2012-05-10 18:39:29 → 
  Size: 931
  Editor: KeithLofstrom
  Comment:
+   ← Revision 10 as of 2013-02-24 21:54:35 → ⇥
  Size: 1722
  Editor: KeithLofstrom
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 3:
-Most of the mass of particles in server sky orbits is [[ http://www.johnstonsarchive.net/physics/RBtutorial.pdf | cold (<1eV) plasma ]], in the upper fringes of the atmosphere.  The total mass of these particles is still very small.  Here is the density versus radius:

{{ attachment:plasmasphere.png ]]
+|| {{ attachment:plasmasphere.png }} || Most of the mass of particles in server sky orbits is [[ http://www.johnstonsarchive.net/physics/RBtutorial.pdf | cold (<1eV) plasma ]], in the upper fringes of the atmosphere.  The total mass of these particles is small.  This plot shows density versus distance.  <<BR>><<BR>> This plot is modified from http://plasmasphere.nasa.gov/media/meridianswing.html ||
-Line 11:
+Line 9:
+||<-6> Earth                                                               || 1.1e12 km^3^ || 6e24 kg  ||
||<-6> Troposphere                                                         ||   8e9 km^3^  || 5e18 kg  ||
 Line 14:
-MORE LATER
+MoreLater
 Line 16:
-http://plasmasphere.nasa.gov/media/meridianswing.html
+== The magnetosphere ==

The dipole field at the equator is 31000nT.  A geomagnetic storm changes this by depositing a westward ring of electric current, which induces a negative change in the field:

||  -30nT to  -50nT ||     weak storm ||
||  -50nT to -100nT || moderate storm ||
|| > -100nT         || intense        ||
|| > -300nT         || "a few times per solar cycle ||
 . Shrivjer and Siscoe "Heliophysics" pp265 Cambridge 2010
 . Also see www.nerc.com/files/GMD_Workshop_Report_April_2011.pdf (chair Don Watkins BPA)

Diff for "Plasmasphere"

The Plasmasphere

The magnetosphere