Can objects "catch up" with their own photons? I have a strange question concerning whether objects can "catch up" with their own photon omissions. By this I don't mean actually catch up to them, just get closer. I'll first use an example using sound to illustrate what I'm asking. Consider two objects, one moving relatively slow and the other moving 90% the speed of sound. All other things be equal, one would expect to hear the slower object at a greater distance from the observer. What about the same scenario with light? The faster object moving 90% the speed of light and being watched for optically. Would the slower object be detected at a greater range? Or would the faster object be seen at the exact same range as the slower, only more blue looking? I'm not a physicist, but I just know since light is involved the obvious answer isn't. -Thanks!