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When we observe distant stars, we are actually seeing the light that was emitted by those stars in the past. Light travels at a finite speed, and the distance between stars and us is so vast that it takes a significant amount of time for the light to reach us. For example, it takes about 4.2 years for light from the nearest star system, Alpha Centauri, to reach us.

In the scenario you mentioned, if light has traveled halfway from a star to us, it means that the light has already been emitted by the star and has traveled a significant distance. However, we wouldn't be able to see it coming towards us because we receive light only when it reaches our location.

To put it simply, seeing an object or a star requires the light emitted by that object to reach our eyes or telescopes. If the light hasn't reached us yet, we won't be able to observe it. So, even if light has traveled halfway, we won't see it until it completes its journey and reaches us.

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