The Allen Telescope Array is designed to listen for signals sent or generated by extraterrestrial life. It has been used in SETI searches since 2007. Credit: Seth Shostak/SETI Institute (CC BY 3.0) Humanity has spent eons looking up at the stars and wondering whether we’re alone, or if there are others like us out there in the vast unknown. Our curiosity has only increased as we have become a technological civilization capable of scanning the heavens for potential signs or signals from other civilizations, called technosignatures. But despite our advancements and intensive searches, we have yet to receive a definitive signal from intelligent life beyond Earth. Why is that? What does the silence tell us? And what would it mean if we stopped listening? This section of the Great Observatories Origins Deep Survey, imaged by the Hubble Space Telescope and capturing thousands of galaxies, shows just how vast the universe is — suggesting some of the many challenges in reaching out to others.…