For centuries, humans measured time in days and years, never imagining that the Universe itself had an age. The discovery of its true timeline began on Earth, not in space. In the late 1700s, Scottish geologist James Hutton observed how rivers carved valleys and sediments formed rock layers - realizing that the Earth’s story stretched far beyond a few thousand years.

By the 19th century, Charles Lyell expanded this understanding, suggesting that Earth’s slow geological changes implied millions of years of evolution. Scientists later used ancient rocks, radioactive decay, and cosmic clues to refine this timeline.

Then came the cosmic breakthrough - astronomers studying distant galaxies noticed they were moving away, proving the Universe was expanding. This discovery, combined with the afterglow of the Big Bang (cosmic microwave background radiation), helped scientists calculate the Universe’s current age: about 13.8 billion years.

From rocks beneath our feet to the dying light of ancient stars, humanity pieced together the timeline of everything - a story written across time and space.