Squeeze Earth's 4.5 billion years into a single 24-hour day. Homo sapiens shows up around 11:59:54 p.m., roughly six seconds before midnight. All of written history, from Sumerian tablets to today, fits into the final tenth of a second. A cosmic blink.
Around 2300 BCE, Enheduanna, daughter of King Sargon of Akkad, became high priestess of the Moon god at Ur. She composed hymns to the goddess Inanna and put her name to them. She is the oldest person identified as the author of a literary work, about 1,500 years before Homer.
The dome of the Pantheon in Rome, finished around 125 CE, is still the world's largest unreinforced concrete dome nearly 1,900 years later. In 2023, MIT researchers showed the Romans hot-mixed quicklime: small lumps of lime react with seeping water and fill in cracks.