Mark J. Harasymiw 
Matemáticas en el Sol (Math on the Sun) [PDF ebook] 

The sun“s importance to Earth and the solar system can“t be exaggerated; it“s the linchpin for life itself. The sun“s structure, atmosphere, and other features are introduced in collaboration with related mathematical problems in this noteworthy companion to the elementary science and math curricula. Readers discover fascinating facts about the sun such as its age: it“s 4.6 billion years old. Engaging text and motivating math problems make learning fun. Amazing photographs and illustrations highlight the awesome power of the sun and add to the volume“s appeal.