Final answer:
Scientists describe the concept of position in scientific terms by using a reference frame, such as Earth, and describing the position of an object relative to stationary objects in that frame.
Step-by-step explanation:
To describe the concept of position in scientific terms, scientists use the idea of a reference frame. A reference frame is an arbitrary set of axes from which the position and motion of an object are described. Earth is often used as a reference frame, and the position of an object is described relative to stationary objects on Earth. For example, a rocket launch could be described in terms of the position of the rocket with respect to Earth as a whole.