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--- ft:planets:gravity [2015/04/26 16:08] – sam
+++ ft:planets:gravity [2015/04/27 18:05] (current) – sam
@@ Line 24: / Line 24: @@
   - Move the ship as normal.
-As an example, consider the NAC ship _Aggressor_ that is performing a flyby of the Earth. At the start of its movement it is within 3" of the Earth, moving at a velocity of 8" mostly parallel to its surface.
+==== Movement Example ====
+=== Step One: Work out gravitational force ===
+As an example, consider the NAC ship //Aggressor// that is performing a flyby of the Earth. At the start of its movement it is within 3" of the Earth, moving at a velocity of 8" mostly parallel to its surface.
 {{ :ft:gravity_1.png?nolink |}}
-According to the table above, the ship is in 4" zone, so will have a gravitational thrust of 4 applied to it. At no point during this example will the _Aggressor_ use its own drives - all movement changes will be entirely due to the Earth.
+Since the //Aggressor// is in the 2"-4" zone, the gravitational force on it applies a thrust of 4. At no point during this example will the //Aggressor// use its own drives - all movement changes will be entirely due to the Earth.
+=== Step Two: Work out direction of force ===
+We next work out which direction the force of gravity applies. This is always in the direction from the ship's starting location towards the centre of the planet.
 {{ :ft:gravity_2.png?nolink |}}
-We find the vector from the _Aggressor_ to the centre of the Earth.
+We find the vector from the //Aggressor// to the centre of the Earth. This is the direction that the ship is being dragged towards the planet - the direction is always taken from the start of movement. Since the gravitational thrust is 4", we apply a vector of 4" to the destination point in the same direction.
+=== Step Three: Determine final vector ===
+{{ :ft:gravity_3.png?nolink |}}
+=== Step Four: Move the ship ===
+{{ :ft:gravity_4.png?nolink |}}