On this date in 1961, about 1,500 C.I.A.-trained Cuban exiles launched a botched invasion of Cuba and failed to overthrow the government of Fidel Castro.

On this date in 1970, three years after N.A.S.A. let three Apollo 1 mission astronauts die,

its Apollo 13 mission was crippled by the explosion of a liquid-oxygen tank after four-fifths of the journey to Earth’s moon.

On this date in 1865, Confederate Army General Robert Lee surrendered his army to Union Army General Ulysses Grant in Virginia.