H. Beam Piper 
Four-Day Planet [PDF ebook] 

Imagine living on a planet with only four "days" each year. That’s the unusual environment of the world known as Fenris, where human inhabitants have to deal with problems like blistering sunlight, freezing nights, and a bevy of horrifying native monsters and other creatures. The story, told through the eyes of a teenager who’s a self-styled investigative reporter, delves into the market pressures causing sharp social divisions on the planet. This prescient tale will please fans of politically oriented science fiction.