The Earth is always spinning on an imaginary line called an axis. This line goes through the North and South poles. We call this spinning, rotation, and it takes about 24 hours for the Earth to make ...

Rudolf Julius Arnheim, psychologist and visual theorist: born Berlin 15 July 1904; married 1943 Annette Siecke (one daughter deceased; marriage dissolved), 1953 Mary Frame (died 1999); died Ann Arbor, ...