Mark J. Harasymiw 
Math in the Asteroid Belt [PDF ebook] 

The asteroid belt between Mars and Jupiter is an intriguing area of our solar system. Scientists have counted over 670, 000 known asteroids there, but there could be millions more not yet found. Readers will discover much more about the asteroid belt in this high-interest book, which blends science and math. They’ll read about several topics, such as space missions to the asteroid belt and the difference between an asteroid and a planet, and solve associated math problems-just like actual space scientists do!