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If photons have a speed limit (speed of light), what happens when you shoot photons through a flashlight but you yourself already have some speed? Do the photons from the flashlight only travel at [speed of light]-[your speed]?
Example: if solar system, galaxy and earth rotation movements were nonexistent and only earth orbital speed existed (30000 m/s), and you were to shoot photons in the approximate same direction the orbital movement is pointing at one time, would the speed of those photons be 299792458 - 30000 = 299762458 m/s ?
If that's the case isn't it possible to determine all movements the earth is suffering in relation to whatever object by measuring the speed of light in various directions over some amount of time?