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||[[attachment:radiosaturn_cassini_big.jpg|{{attachment:radiosaturn_cassini_big.jpg|rings of Saturn viewed from NASA Cassini probe|width=500}}]]||Rings of saturn viewed from NASA Cassini probe. Click for larger image. False-color green bands are ring particles larger than 5cm, perhaps 10 grams or larger, which have survived intact for millions or billions of years|| ||[[attachment:radiosaturn_cassini_big.jpg|{{attachment:radiosaturn_cassini_big.jpg|rings of Saturn viewed from NASA Cassini probe|width=400}}]]||Rings of saturn viewed from NASA Cassini probe. Click for larger image. False-color green bands are ring particles larger than 5cm, perhaps 10 grams or larger, which have survived intact for millions or billions of years||

Ring Debris

Some folks worry about billions or trillions of thinsats turning into a vast cloud of space debris. This is not a problem with proper choice of orbits, and active, complete life cycle management of thinsats.

traditional
satellites

server sky
thinsats

altitude

300 km

6400 km

inclination

0-110°

0-0.25°

fuel supply

2 - 10 years

infinite

orbit assignment

ad hoc

coordinated

orbit management

per satellite

entire system

tracking accuracy

1 km

0.1mm

orbit velocity

8 km/s

5 km/s

closing velocity

16 km/s

<< 1 m/s

threat avoidance

none

continuous

vulnerability

single point

redundant

end-of-life

derelict

recycle as ballast

rings of Saturn viewed from NASA Cassini probe

Rings of saturn viewed from NASA Cassini probe. Click for larger image. False-color green bands are ring particles larger than 5cm, perhaps 10 grams or larger, which have survived intact for millions or billions of years

An example of a system that is not subject to continuous bombardment are the rings of Saturn. Parts of the rings subject to frequent collisions, with particle sizes less than 1cm, but other regions of the rings have particle sizes larger than 5 centimeters. These particles are snowballs, very fragile - they would fragment into tiny flakes and not survive as snowballs if they were continuously colliding at high speed for hundreds of millions of years. Ring snowballs are placed randomly, cannot not maneuver, cannot detect threats, and are unmanaged, yet they survive for vast timescales. Server sky orbits are designed with "rules of the road" that almost eliminate collisions with orbital mechanics, with additional layers of tracking, control, and survivability that the snowballs (and traditional satellites) do not have.

RingDebris (last edited 2012-12-01 18:10:10 by KeithLofstrom)