Light's speed never changes, no matter what
Light's speed in a vacuum is a constant 299,792 kilometers per second, unaffected by its source's motion—a revolutionary idea that reshaped our understanding of the universe.
The speed of light in a vacuum is always the same, about 299,792 kilometers per second. This universal constant doesn't speed up or slow down, even if its source is moving. Albert Einstein first proposed this revolutionary idea in 1905, challenging classical physics which assumed speeds would simply add up.
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