April 22, 2017, marks the 47th anniversary of Earth Day—a day intended to inspire awareness and appreciation for the Earth's natural environment. Organizers started Earth Day in response to a…
(Encyclopedia) April Fool's Day or All Fool's Day, holiday of uncertain origin, known for practical joking and celebrated on the first of April. Prior to the adoption of the Gregorian calendar in…
(Encyclopedia) John Day Dam, 219 ft (67 m) high and 5,640 ft (1,719 m) long, on the Columbia River between Oregon and Wash.; built between 1959 and 1968 by the U.S. Army Corps of Engineers. It is an…
(Encyclopedia) Hershey, Alfred Day, 1908–1997, American microbiologist, b. Owosso, Mich., Ph.D., Michigan State College (now Michigan State Univ.), 1934. Hershey was a professor at the Washington…
(Encyclopedia) Julian Day calendar, system of astronomical dating that allows the difference between two dates to be calculated more easily than conventional civil calendars with their uneven months…
(Encyclopedia) All Souls' Day, Nov. 2 (exceptionally, Nov. 3), feast of the Roman Catholic Church on which the church on earth prays for the souls of the faithful departed still suffering in…
(Encyclopedia) All Saints' Day, feast of the Roman Catholic and Anglican churches, and day on which churches glorify God for all God's saints, known and unknown. It is celebrated on Nov. 1 in the…
