How big is a golf ball?
A regulation golf ball must be at least 42.67 millimeters (1.68 inches) in diameter and weigh no more than 45.93 grams (1.62 ounces).
These limits are set by golf's governing bodies, the R&A and the United States Golf Association. There is no maximum size or minimum weight, but a larger or lighter ball would fly shorter and be harder to control, so almost all golf balls are made at or near the limits.
Modern golf balls have a rubber core surrounded by one or more layers and a cover, usually made of a material called urethane or a type of plastic called ionomer. Multi-layer balls are designed to fly far off the tee but spin more around the greens. Golf balls are tested strictly for speed and distance before being approved for competition.
History
Early golf balls were wooden. In the 1600s, players switched to featheries, leather pouches stuffed with boiled feathers. These were replaced in the 1850s by the gutta-percha ball made from tree sap, and around 1900 by rubber-core balls similar to today's.
Did You Know?
In 1971, astronaut Alan Shepard hit two golf balls on the Moon during the Apollo 14 mission.