On this date

In 1937, American composer and pianist George Gershwin died at a Los Angeles hospital of a brain tumor; he was 38.

In 1955, the U.S. Air Force Academy swore in its first class of cadets at its temporary quarters at Lowry Air Force Base in Colorado.

In 1960, the novel “To Kill a Mockingbird” by Harper Lee was first published by J.B. Lippincott and Co.

In 1977, the Presidential Medal of Freedom was presented to polio vaccine pioneer Jonas Salk and (posthumously) to Rev. Martin Luther King Jr. by President Jimmy Carter.

In 1979, the abandoned U.S. space station Skylab made a spectacular return to Earth, burning up in the atmosphere and showering debris over the Indian Ocean and Australia.

In 1989, actor and director Laurence Olivier died in Steyning, West Sussex, England, at age 82.

In 1995, the U.N.-designated “safe haven” of Srebrenica in Bosnia-Herzegovina fell to Bosnian Serb forces, who then carried out the killings of more than 8,000 Muslim men and boys.

Ten years ago: Lady Bird Johnson, the former first lady who’d championed conservation and worked tenaciously for the political career of her husband, President Lyndon B. Johnson, died in Austin, Texas, at age 94. Five years ago: Donald J. Sobol, 87, author of the popular “Encyclopedia Brown” series of children’s mysteries, died in Miami.

One year ago: Two bailiffs at the Berrien County, Mich., courthouse were shot to death by a jail inmate during an escape attempt; the inmate was also killed.