Galaxy NGC 4845 is located 65 million light-years away, meaning that we are seeing it as it was 65 million years ago, right around the time the T. rex went extinct. The finite speed of light has the exact same effect in the other direction: If there are intelligent aliens in this galaxy, when they look at the Milky Way, they are seeing our galaxy as it was at the time of the dinosaurs. In principle, they could see our planet as it was at that time, too.⁠ ⁠ But, one huge caveat. Seeing the Milky Way as it was at the time of the dinosaurs is not the same as actually being able to see individual dinosaurs! Using current technology, astronomers cannot resolve any details on even the biggest planets orbiting the nearest stars. Dinosaurs are much smaller than a whole planet, and NGC 4845 is millions of times farther away.⁠ ⁠ _____⁠ ⁠ Even the wildest theoretical technologies that anybody has ever imagined (such as using the Sun as a magnifying gravitational lens) would not be nearly powerful...