Mathematicians and online experts often highlight how folding a standard sheet of paper 42 times could theoretically match the Earth-Moon distance. This exponential growth principle is fascinating—but practically unachievable.
Educational platforms like Maths en Direct demonstrate this concept clearly. Consider a standard A4 sheet, just 0.1 mm thick. Folding it 42 times would yield a thickness exceeding the average Earth-Moon distance of 384,400 km, which fluctuates between 356,700 km and 406,300 km.
Note: This is the lunar distance, distinct from the astronomical unit (AU)—roughly 150 million km from Earth to the Sun.
Each fold doubles the thickness. After three folds: 0.1 × 2 × 2 × 2 = 0.1 × 23 = 0.8 mm. Extending this to 42 folds: 0.1 × 242 = 439,804,651,110.4 mm, or over 439,804 km.
A Quora engineer confirms: 242 layers (4,398,046,511,104 thicknesses, or 4.4 trillion) × 0.1 mm = 439,804,651.1104 m—far surpassing the Moon's distance.
Theoretically sound, yet impossible in practice. The folded stack's surface area shrinks exponentially, and most people struggle to fold A4 paper more than 7-8 times by hand.
As forum user Touko on Secouchermoinsbete notes: "This reasoning is infinite: Crush a Carambar to reach Saturn, or unfold couscous atoms to circle Earth a million times… mind-blowing!"
Explore this further in TED-Ed's explanatory video from 2021:
