A rocket to the moon

 

1. When sending a rocket to the moon, the Earth is .. considered the frame of reference, 
2. 
   
3. meaning we would measure the rocket's motion relative to the Earth, not the moon itself; 
4. 
   
5. this is because the Earth is considered relatively stationary compared to the moving rocket on its trajectory towards the moon. 
6. 
   
7. relatively - in relation to each other   -  Earth and rocket
8.  
9. stationary - standing still - motionless

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