De revolutionibus orbium coelestium divided into six "books" (sections or parts), following closely the layout of Ptolemy's "Almagest" which it updated and replaced: Copernicus argued that the universe comprised eight spheres. The outermost consisted of motionless, fixed stars, with the Sun motionless at the center. The known planets revolved about the Sun, each in its own sphere, in the order: Mercury, Venus, Earth, Mars, Jupiter, Saturn. The Moon, however, revolved in its sphere around the Earth. What appeared to be the daily revolution of the Sun and fixed stars around the Earth was actually the Earth's daily rotation on its own axis. Copernicus adhered
Canticle of the Sun Kõrvits (1969) composed a 12-part "A cappella" piece for mixed choir (SSAATTBB) "The Canticle of the Sun" for Southern Chorale choir in 2014. Pope Francis published his second encyclical Laudato si' on June 18, 2015. The Canticle inspired the encyclical's title, "Praise be to you," and was quoted in the first paragraph, "Praise be to you, Our Lord, through our Sister, Mother Earth, who sustains and governs us, and who produces various fruits, with colored flowers and herbs." The Irish composer Vincent Kennedy was commissioned by the Irish Franciscans to set the Canticle of the Sun for Soprano, Harp and