Arcturus: Facts About the Bright Red Giant Star
Arcturus is a red giant star in the Northern Hemisphere of Earth's sky and the brightest star in the constellation Boötes (the herdsman). Arcturus is also among the brightest stars that can be seen from Earth. Astronomers say Arcturus will end up as a white dwarf at the end of its life.
The easiest way to spot Arcturus is by following the curve of the "handle" of the Big Dipper (Ursa Major). A simple way to remember how to find the star is to recall the famous phrase "Follow the arc to Arcturus and then speed on to Spica." The latter part of that phrase refers to the bright star Spica, which is actually a binary star.
Organizers for the Chicago World's Fair in 1933 were searching for a memorable way to open their exhibit. The previous world's fair in the city had occurred 40 years earlier, in 1893. Because at the time, Arcturus was believed to be about 40 light-years away from Earth, the fair's organizers hit upon the idea of using the star's light as a part of the new exhibition and as a way to commemorate the previous Chicago World's Fair.
At 9:15 p.m. Central Time on May 27, 1933, telescopes focused the star's light on several photoelectric cells. The electric current from the star-powered photo cells was used to flip a switch that turned on the floodlights at the exhibition grounds.
