public void EarthOrbit()
{
var world = new MockUniverse();
var universe = Universe.Builder.Build(world.Universe).Materialise();
var sol = universe.StarClusters
.SelectMany(x => x.SolarSystems)
.Single(x => x.Id == world.SolarSystem.ObjectId);
var earth = sol.Satellites
.Single(x => x.Id == world.Earth.ObjectId);
var context = new TickContext(0) { ElapsedTicks = 60 * 60 * 5 };
var orbiter = new Orbiter(sol);
var orbitRadius = earth.Position.LocalCoordinates.Magnitude;
for (var i = 0; i < 12*21; i++)
{
orbiter.Orbit(context);
Console.WriteLine("{0}: {1:n}", i, earth.Position.LocalCoordinates * 1e-5);
earth.Position.LocalCoordinates.Magnitude.ShouldBe(orbitRadius, Units.Tolerance*100);
}
}