A regulation NFL football must be inflated to between 12.5 and 13.5 psi.

The Boston Marathon is the world's oldest annual marathon, first held in 1897.

Particles can exist in multiple states until observed.

Facial expressions are recognized across many cultures.

The Siege of Troy is a legendary conflict described in Greek epic poetry.

Weightlifter Lasha Talakhadze set a world record by lifting 265 kg in the clean and jerk at the 2021 Tokyo Olympics.

Roman gladiatorial games were often less lethal than popular culture suggests — gladiators were expensive to train.

Sourdough bread is made from a 'starter' — a live culture of wild yeast and bacteria that can be maintained for decades.

Particles can exist in multiple states until observed.