The Voyager explorers, which provided scientists and the world with the first detailed pictures of faraway planets, were designed and tested during 1972 to 1977. The two most intelligent machines ever built in the NASA space program, the explorers were launched from Cape Canaveral, Fla., in 1977. Voyager 2 was launched first on August 20, followed by Voyager 1 on September 5.
Steam and the inexpensive electricity it could produce brought about dramatic technical growth in the United States. Developed during the last century, reliable and efficient steam engines were the forerunners of today's massive generating facilities. A rare survivor of the period, the Pratt facility is the oldest generating plant of its kind in the Northeast and embodies the typical features of engines in a row, open-front marble switchboard, and an observation balcony at street level.
On April 21, 1949, a completely outdoor turbine-generator was placed into commercial operation at the Greens Bayou electric power plant--the first fully outdoor unit to operate in the United States. The demand for unprecedented quantities of electricity after World War II pressed utilities to provide addition power quickly. The outdoor design, unlike the traditional large turbine hall, resulted in significant reductions in the cost per kilowatt to build the plant.
This run-of-the-river plant is a typical example of late nineteenth-century small-scale (750 kilowatt) low-head hydroelectric power technology. The Fries Manufacturing and Power Company began operating the Idol's Station on April 18, 1898, making it the first commercial hydroelectric plant in North Carolina involving long-distance power transmission, fourteen-miles distance at 10,000 volts. Idol's was an important power source for transportation, lighting, and industry in the Winston-Salem area.