Robert G Keefer (born 1916)

In 1916, in the year that Robert G Keefer was born, the Battle of Verdun was fought from February through December. It was the largest and longest battle of World War I, lasting 303 days. The original estimates were 714,231 casualties - 377,231 French and 337,000 German, an average of 70,000 casualties a month. Current estimates are even larger. The Battle of the Somme was also fought from July through September of the same year. Original estimates were 485,000 British and French casualties and 630,000 German casualties.

In 1952, on July 2, Dr. Jonas E. Salk tested the first dead-virus polio vaccine on 43 children. The worst epidemic of polio had broken out that year - in the U.S. there were 58,000 cases reported. Of these, 3,145 people had died and 21,269 were left with mild to disabling paralysis.

In 1960, on May 1st, an American CIA U-2 spy plane, piloted by Francis Gary Powers, was shot down by a surface-to-air missile over the Soviet Union. Powers ejected and survived but was captured. The U.S. claimed that the U-2 was a "weather plane" but Powers was convicted in the Soviet Union of espionage. He was released in 1962 after 1 year, 9 months and 10 days in prison.

In 1979, on March 28th, a partial nuclear meltdown occurred at the power plant at Three Mile Island Pennsylvania. Radiation leaked into the environment, resulting in a rating of 5 on a scale of 7 ("Accident With Wider Consequences") . It ended up costing $1 billion to clean up the site.

In 1990, on April 24th, the Hubble telescope was launched into space after long delays due to the Challenger explosion. An optical flaw was found within weeks of launch but was fixed within three years. The discoveries made possible by the Hubble have contributed to scientists' understanding of the universe.