It is the 14th century, and one of the most apocalyptic events in human history is set to occur - the coming of the Black Death. History teaches us that a third of Europe's population was destroyed. But what if the plague had killed 99 percent of the population instead? How would the world have changed? This is a look at the history that could have been - a history that stretches across centuries, a history that sees dynasties and nations rise and crumble, a history that spans horrible famine and magnificent innovation.

Welcome to Ringworld, an intermediate step between Dyson Spheres and planets. The gravitational force created by a rotation on its axis of 770 miles per second means no need for a roof. Walls 1,000 miles high at each rim will let in the sun and prevent much air from escaping. Larry Niven's novel, Ringworld, is the winner of the 1970 Hugo Award for Best Novel, the 1970 Nebula Award for Best Novel, and the 1972 Ditmars, an Australian award for Best International Science Fiction.

Winner of the Nebula Award for Best Novel, Red Mars is the first book in Kim Stanley Robinson's best-selling trilogy. Red Mars is praised by scientists for its detailed visions of future technology. It is also hailed by authors and critics for its vivid characters and dramatic conflicts.

For centuries, the red planet has enticed the people of Earth. Now an international group of scientists has colonized Mars. Leaving Earth forever, these 100 people have traveled nine months to reach their new home. This is the remarkable story of the world they create - and the hidden power struggles of those who want to control it.

Adrian Tchaikovksy's critically acclaimed stand-alone novel Children of Time is the epic story of humanity's battle for survival on a terraformed planet. Who will inherit this new Earth? The last remnants of the human race left a dying Earth, desperate to find a new home among the stars. Following in the footsteps of their ancestors, they discover the greatest treasure of the past age - a world terraformed and prepared for human life. But all is not right in this new Eden.

Sixteen-year old Hazel lives in the Daedalus, a starship that is flying in search of a new world. The ship has been traveling for 500 years, searching for a world to settle in after having to abandon its last world. Everyone on board Daedalus lives a very simple existence in farming villages. The age of machines supplying their needs was lost during a mutiny 500 years ago.