“The near side of a galaxy is tens of thousands of light-years closer to us than the far side; thus we see the front as it was tens of thousands of years before the back. But typical events in galactic dynamics occupy tens of millions of years, so the error in thinking of an image of a galaxy as frozen in one moment of time is small.”

American astronomer and science communicator of the mid-to-late 20th century, Carl Sagan made complex cosmic concepts accessible to the public through his books and television series. He championed scientific skepticism and the search for extraterrestrial life, blending rigor with poetic clarity to inspire wonder about humanity’s place in the universe.