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Could We Position Telescopes To Watch The Past Like a Movie?
A question that has bothered me for years
One of the most well known parts of astronomy is the fact that the farther you look into space, the farther you peer into the past. Light takes time to travel. Sometimes it takes a very, very long time to get where it is going. The light from the sun, for example, takes roughly eight minutes to leave the surface of the star and reach the surface of the Earth. That means if the sun were to be snuffed out in an instant, it would take us eight minutes to know anything was wrong. If you move farther out, the same is true. If Earth’s nearest star were to extinguish itself in a moment, it would take us years to notice its absence.
But can this property work in reverse? If you managed to place a powerful telescope at an appropriate distance from Earth, could you witness the past? Say you managed to put an incredibly powerful telescope 300 light years from Earth. Could you watch the happenings on Earth as they occurred 300 years ago?
The theory works like this. If we invented a way to travel across space instantaneously and we warped ourselves to a point 123 light years away and honed in on Earth, would the light show us Earth as it looked in 1900? This question has fascinated me and tickled my brain for years, and I have finally…
