May 5, 1961 – Alan Shepard became the first American in space. He piloted the spacecraft Freedom 7 during a 15-minute 28-second suborbital flight that reached an altitude of 116 miles (186 kilometers) above the earth. Shepard’s success occurred 23 days after the Russians had launched the first-ever human in space, cosmonaut Yuri Gagarin, during an era of intense technological competition between the Russians and Americans called the Space Race.
Birthday – Explorer Robert E. Peary (1856-1920) was born in Cresson, Pennsylvania. He organized and led eight Arctic expeditions and reached the North Pole on April 6, 1909. In another expedition, he proved Greenland is an island. He also proved the polar ice cap extends beyond 82° north latitude, and discovered the Melville meteorite.
Sir John Frederick William Herschel, 1st Baronet (born March 7, 1792, Slough, Buckinghamshire, England—died May 11, 1871, Collingwood, Kent), English astronomer and successor to his father, Sir William Herschel, in the field of stellar and nebular observation and discovery.
19 February 1473 – 24 May 1543, Nicolaus Copernicus, Polish astronomer; Latinised name of Mikołaj Kopernik. He proposed a model of the solar system in which the planets orbited in perfect circles around the sun, and his work ultimately led to the overthrow of the established geocentric cosmology. He published his astronomical theories in “De Revolutionibus Orbium Coelestium” (‘On the Revolutions of the Celestial Spheres’) released 1543, the year he died.