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**Unformatted text preview: **Runge-Kutta Integrator You will write a Runge-Kutta integrator to calculate the evolution of an earth/sun system. Let the position of the the earth be ( x e ( t ) , y e ( t )) and the position of the sun be ( x s ( t ) , y s ( t )) . These variables satisfy the following system of second order equations, ¨ x e ¨ y e ¨ x s ¨ y s = ( Gm s ) / | r | 2 (- ˆ r x ) ( Gm s ) / | r | 2 (- ˆ r y ) ( Gm s ) / | r | 2 (ˆ r x ) ( Gm s ) / | r | 2 (ˆ r y ) where the two dots represent the second derivative with respect to t , G = 6 . 67 × 10- 11 Nm 2 / kg 2 is the gravitational constant, m e = 5 . 97 × 10 24 kg is the mass of the earth, m s = 1 . 99 × 10 30 kg is the mass of the sun, r is a vector from the sun to the earth, and ˆ r = r/ | r | . For the initial conditions, let the sun be located at the origin with zero velocity, and let the earth be located at (1 . 50 × 10 11 , 0) (the units are m) with velocity...

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