Which describes what an outside observer at rest would observe about a spaceship that speeds up and approaches the speed of light?

According to special relativity, an observer at rest sees a moving spaceship’s clock run more slowly than their own (time dilation). The observer also measures the spaceship as shorter along its direction of motion (length contraction); as its speed approaches the speed of light, both effects become more pronounced. Therefore, time moves more slowly on the spaceship and its length decreases.

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