Suppose there is intelligent life elsewhere in the Universe. The odds, of course, are greatly in favor of this assumption.
Now suppose that there is a planet containing life that is close enough to be able to see the light being reflected off of Earth with whatever telescopic powers these lifeforms have available to them.
Suppose, even, that this planet is in the Andromeda Galaxy, the closest to the Milky Way, approximately 2.5 million light years away.
This means that the light that these intelligent creatures are viewing is old. Very old.
They are seeing light from an earth that is nothing but distant history to us – the first appearance of the genus Homo.
They are seeing history.
They are seeing Earth’s past.
They won’t see today’s light for another 2.5 million years.
Kind of makes you feel insignificant, doesn’t it?