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⇤ ← Revision 1 as of 2014-11-06 02:41:22
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| || "zone" || density kg/m^3^|| pressure || | || "zone" || density kg/m^3^|| pressure || || zepto || 1e-21 || || || || || zepto || 1e-20 || || || interplanetary space || || atto? || ? || || 35786 km altitude || geosynchronous orbit || || atto || 6e-18 || || 6411 km altitude || m288 server sky || || atto || 3e-17 || || || beamline Large Hadron Collider || || femto || 1e-15 || || 1250 km altitude || lowest sustainable solar sail || || pico || 2e-12 || || 410 km altitude || International Space Station || || nano || 1.2e-09 || || 160 km altitude || useful low earth orbits || || micro || 6.8e-07 || || 100 km altitude || "edge of space", suborbitals || || micro || 8.5e-06 || || 85 km altitude || drag zone for suborbital || || milli || 1.1e-03 || || 50 km altitude || || || || 1.2 || 1.01 Bar || 0 km altitude || Sea level || || || 1.2 || 1.01 Bar || 0 km altitude || Sea level || |
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| || Kilo || ≈ 1e3 || 1.1 KBar || Deepest Ocean || ideal gas density at pressure || || || 1.2 || 1.01 Bar || 0 km altitude || Sea level || || milli || 1.1e-03 || || 50 km altitude || || || micro || 6.8e-07 || || 100 km altitude || "edge of space", suborbitals || || nano || 1.2e-09 || || 160 km altitude || useful low earth orbits || || pico || 2e-12 || || 410 km altitude || International Space Station || || femto || 1e-15 || || 1250 km altitude || lowest sustainable solar sail || || atto || 3e-17 || || || beamline Large Hadron Collider || || atto || 6e-18 || || 6411 km altitude || m288 server sky || || atto? || ? || || 35786 km altitude || geosynchronous orbit || || zepto || 1e-20 || || || interplanetary space || || zepto || 1e-21 || || || || |
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| The air is too dense at ISS altitudes (in the pico zone) to experiment with server sky - thinsats must be in orbit long enough to test maneuvering and to be observed from the earth, in the femto circular orbit zone or higher. Low earth orbits in the nano zone have a million times as much drag, and a suborbital in the micro zone has a billion times as much density, though it may briefly come to a stop in a vertical trajectory. | The air is too dense at ISS altitudes (in the pico zone) to experiment with server sky - thinsats must be in orbit long enough to test maneuvering and to be observed from the earth, in the femto circular orbit zone or higher. Low earth orbits in the nano zone have a million times as much drag, and a suborbital in the micro zone has a billion times as much density as the femto zone. A suborbital falling for 100 seconds is moving at more than 900 meters per second, and would descend almost 50 kilometers, into the "milli zone". A single turn and stop thinsat maneuver takes 300 seconds. Quite impractical. |
A Density Scale
Density
Server Sky will deploy at 6411 km altitude. Gas density at that altitude is 6E-18 kg/m2, mostly hydrogen. That is 5E-18 times smaller than air density at the surface; it is difficult to comprehend just how tenuous the exosphere is, so here is a density scale. The densities below assume average solar activity, F107 = 150 , averaged over the day, on the equator, at the equinox .
"zone" |
density kg/m3 |
pressure |
||
zepto |
1e-21 |
|
|
|
zepto |
1e-20 |
|
|
interplanetary space |
atto? |
? |
|
35786 km altitude |
geosynchronous orbit |
atto |
6e-18 |
|
6411 km altitude |
m288 server sky |
atto |
3e-17 |
|
|
beamline Large Hadron Collider |
femto |
1e-15 |
|
1250 km altitude |
lowest sustainable solar sail |
pico |
2e-12 |
|
410 km altitude |
International Space Station |
nano |
1.2e-09 |
|
160 km altitude |
useful low earth orbits |
micro |
6.8e-07 |
|
100 km altitude |
"edge of space", suborbitals |
micro |
8.5e-06 |
|
85 km altitude |
drag zone for suborbital |
milli |
1.1e-03 |
|
50 km altitude |
|
|
1.2 |
1.01 Bar |
0 km altitude |
Sea level |
|
1.2 |
1.01 Bar |
0 km altitude |
Sea level |
Mega |
≈ 1e6 |
3.6 MBar |
Center of Earth |
ideal gas density at pressure |
The air is too dense at ISS altitudes (in the pico zone) to experiment with server sky - thinsats must be in orbit long enough to test maneuvering and to be observed from the earth, in the femto circular orbit zone or higher. Low earth orbits in the nano zone have a million times as much drag, and a suborbital in the micro zone has a billion times as much density as the femto zone.
A suborbital falling for 100 seconds is moving at more than 900 meters per second, and would descend almost 50 kilometers, into the "milli zone". A single turn and stop thinsat maneuver takes 300 seconds. Quite impractical.