COLORADO SPRINGS, April 1 (UPI) -- The seven "planets" of antiquity will line up in Thursday evening's sky in an occurrence not to be seen again for 32 years, a U.S. astronomer said.
Neil DeGrasse Tyson, director of the American Museum of Natural History's Hayden Planetarium in New York, said before people learned Earth revolved around the sun, the seven naked-eye celestial objects were given special importance because they moved slowly against the background of stars.
The Greeks named the objects planeta, which means "wanderers."
For one more week, Tyson said, the planets will be visible, "one right after another."
The bodies trace a high arc across the sky, from west to east, with the sun setting, Mercury appearing shortly thereafter, then Venus -- the brightest -- Mars, Saturn, the moon and Jupiter.
Tyson, speaking at the National Space Symposium, said the importance of the planets to Western culture remains forever captured in the names of the days of the week, each traceable to Roman and Norse mythologies.
For example, Saturday is named for Saturn, while Sunday is named for the sun and Monday is named for the moon. Tuesday in French is Mardi, for Mars and Wednesday is Mercredi, for Mercury. Thursday is Jeudi for Jupiter -- Jeuves in Spanish. Friday is Vondredi, for Venus.
The next similar alignment of the sun, moon and visible planets will be in 2036.
