The acknowledgement of extraterrestrial life would might be a shock to religion, but it could be the best thing that ever happened to historians and archeologists. If alien cultures have computing and storage technology that has been following Metcalf’s Law (or whatever they call it) for the past 100 million years, they would have the potential to record and store a complete audio and video record of Earth’s history in their archives. Even if they didn’t bother to record Earth history, they still might have the technology to chase down the light that left Earth a million years ago. Let’s say the aliens traveled across a million light years of space-time to get to Earth. That means that, with advanced optical sensors and recording equipment, they might be able to capture a partial record of Earth’s history as it travels across the universe in the form of light. If they travelled here via some weird bends in space-time, maybe that light is already heading back towards Earth right now!
Einstein proved that space and time are interlinked, so the universe is not uniform in shape. It is not shaped like a sphere or a disk or anything with uniformly-shaped geometry. A beam of light leaving Earth would be lensed by grativational forces that would cause it to travel on a winding journey around other solar systems, black holes, and other clusters of matter or antimatter with sufficient gravitational force to bend space-time. If it were fortunate enough not to hit a dead end in the form of a black hole, it might even loop back upon itself given sufficient pull from a massive object or given enough time and space to gradually move drift one direction rather than another. Who knows where the light from Earth’s history has traveled or how it could still be used?