Every time you open your eyes to look at something, you're literally looking back in time.
Consider: light travels at a speed of 186,000 miles per second (or 300 million meters per second), so if you're looking at someone or something from a distance of one meter, you're seeing it not as it is but as it was three-billionths of a second ago.
Of course, the time it takes light to travel to your eyes is inconsequential in most situations. But that's not the case when you're talking about the vast scale of the cosmos. When you look out into space, you're looking way, way, way back in time. Just check out the video above and/or read the transcript below to find out how. Don't forget to leave your thoughts in the comments below. Talk nerdy to me!
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