The Eternals, the ruling class of the Future, had the power of life and death not only over every human being but over the very centuries into which they were born. Past, Present, and Future could be created or destroyed at will. You had to be special to become an Eternal. Andrew Harlan was special. Until he committed the one unforgivable sin - falling in love. Eternals weren’t supposed to have feelings. But Andrew could not deny the sensations that were struggling within him. He knew he could not keep this secret forever. And so he began to plan his escape.

This classic science fiction masterwork by Isaac Asimov weaves stories about robots, humanity, and the deep questions of existence into a novel of shocking intelligence and heart.

In the 23rd century, pioneers have escaped the crowded earth for life in self-sustaining orbital colonies. One of the colonies, Rotor, has broken away from the solar system to create its own renegade utopia around an unknown red star two light-years from Earth: a star named Nemesis. Now a 15-year-old Rotorian girl has learned of the dire threat that nemesis poses to Earth’s people - but she is prevented from warning them. Soon, she will realize that Nemesis endangers Rotor as well.

A collection of 20 classic short stories by Isaac Asimov, author of the Foundation series, featuring the definitive and only in-print version of “Nightfall”.

Only a few know the terrifying truth - an outcast Earth scientist, a rebellious alien inhabitant of a dying planet, a lunar-born human intuitionist who senses the imminent annihilation of the Sun... They know the truth - but who will listen? They have foreseen the cost of abundant energy - but who will believe?These few beings, human and alien, hold the key to the Earth's survival.

The millions of people around the world who loved What If? still have questions, and those questions are getting stranger. Thank goodness xkcd creator Randall Munroe is here to help. Planning to ride a fire pole from the Moon back to Earth? The hardest part is sticking the landing. Hoping to cool the atmosphere by opening everyone’s freezer door at the same time? Maybe it’s time for a brief introduction to thermodynamics. Want to know what would happen if you rode a helicopter blade, made a lava lamp out of lava, or jumped on an erupting geyser? Okay, if you insist.

Stephen Hawking not only unraveled some of the universe's greatest mysteries but also believed science plays a critical role in fixing problems here on Earth. Now, as we face immense challenges on our planet - including climate change, the threat of nuclear war, and the development of artificial intelligence - he turns his attention to the most urgent issues facing us. Will humanity survive? Should we colonize space? Does God exist? These are just a few of the questions Hawking addresses in this wide-ranging, passionately argued final book from one of the greatest minds in history.

The Battle of Serenity Valley was the turning point that led the Independents to their defeat at the hands of the Alliance. Yet the Browncoats had held the valley for weeks against all odds, before being ordered to lay down their arms. Command stated they refused to send in airpower because the ground war was "too hot". But the soldiers who were there insist that was not true.... While picking up a new cargo on Persephone, Captain Malcolm Reynolds is kidnapped by a bunch of embittered veteran Browncoats who suspect him of sabotaging the Independents during the war.

The world outside has grown toxic, the view of it limited, talk of it forbidden. The remnants of humanity live underground in a single silo. But there are always those who hope, who dream. These are the dangerous people, the residents who infect others with their optimism. Their punishment is simple. They are given the very thing they want: They are allowed to go outside.

The human soldiers stranded on the planet Paradise have been recruited into an alien legion to do the dirty jobs that the high-tech species won't do. Their first mission is to kick the enemy off a backwater planet no one cares about. It's a simple assignment, except everyone has a hidden agenda, and the planet could become a deathtrap.

When an experiment to study quantum uncertainty goes spectacularly wrong, physics student Bill Rustad and his friends find that they have accidentally created an inter-dimensional portal. They connect to Outland - an alternate Earth with identical geology, but where humans never evolved. The group races to establish control of the portal before the government, the military, or evildoers can take it away. Then everything changes when the Yellowstone supervolcano erupts in an explosion large enough to destroy civilization and kill half the planet.

It is fall. CIA analyst Jack Ryan, historian and former Marine, is vacationing in London with his wife and young daughter. Suddenly, right before his eyes, a terrorist group launches its deadly attack. Instinctively, he dives forward to break it up, and is shot. It is not until he wakes up in the hospital that he learns whose lives he has saved - the Duke and Duchess of Kent.

For the better part of five decades, Jerry Pournelle's name has been synonymous with hard-hitting science fiction. For the first time, all of Pournelle's best short work has been collected in a single volume. Herein you will find over a dozen short stories, each with a new introduction by editor and longtime Pournelle assistant John F. Carr, as well as essays and remembrances by Pournelle collaborators and admirers.

Over his four-decade career, Sid Meier has produced some of the world's most popular video games, including Sid Meier's Civilization, which has sold more than 51 million units worldwide and accumulated more than one billion hours of play. Sid Meier's Memoir! is the story of an obsessive young computer enthusiast who helped launch a multibillion-dollar industry.

In a scrap heap within an abandoned factory, the greatest invention in history lies dormant and unused. By what fatal error of judgment has its value gone unrecognized, its brilliant inventor punished rather than rewarded for his efforts? In defense of those greatest of human qualities that have made civilization possible, one man sets out to show what would happen to the world if all the heroes of innovation and industry went on strike.

His name was Biron Farrill and he was a student at the University of Earth. A native of one of the helpless Nebular Kingdoms, he saw his home world conquered and controlled by the planet Tyrann - a ruthless, barbaric Empire that was building a dynasty of cruelty and domination among the stars. Farrill’s own father had been executed for trying to resist the Tyrann dictatorship and now someone was trying to kill Biron. But why? His only hope for survival lay in fleeing Earth and joining the rebellion that was rumored to be forming somewhere in the Kingdoms.

This classic science fiction masterwork by Isaac Asimov weaves stories about robots, humanity, and the deep questions of existence into a novel of shocking intelligence and heart.

The Eternals, the ruling class of the Future, had the power of life and death not only over every human being but over the very centuries into which they were born. Past, Present, and Future could be created or destroyed at will. You had to be special to become an Eternal. Andrew Harlan was special. Until he committed the one unforgivable sin - falling in love. Eternals weren’t supposed to have feelings. But Andrew could not deny the sensations that were struggling within him. He knew he could not keep this secret forever. And so he began to plan his escape.

A collection of 20 classic short stories by Isaac Asimov, author of the Foundation series, featuring the definitive and only in-print version of “Nightfall”.

Only a few know the terrifying truth - an outcast Earth scientist, a rebellious alien inhabitant of a dying planet, a lunar-born human intuitionist who senses the imminent annihilation of the Sun... They know the truth - but who will listen? They have foreseen the cost of abundant energy - but who will believe?These few beings, human and alien, hold the key to the Earth's survival.

Jon Ryan has some unfinished business. Since he caused the universe to reboot, well, he can't seem to find his wife of two billion years. That's one great big oops. He also can't find the massive time ship Aramthella and her human crew. Double oops. And then there's the matter of not knowing whey why there are several copies of key people in the new reality he must navigate. Triple oops. He actually knows one whole heck of a lot less about his current situation than seems healthy. But he's Jon Ryan, former fighter pilot turned android warrior for humankind.

In the 23rd century, pioneers have escaped the crowded earth for life in self-sustaining orbital colonies. One of the colonies, Rotor, has broken away from the solar system to create its own renegade utopia around an unknown red star two light-years from Earth: a star named Nemesis. Now a 15-year-old Rotorian girl has learned of the dire threat that nemesis poses to Earth’s people - but she is prevented from warning them. Soon, she will realize that Nemesis endangers Rotor as well.

What is VALIS? This question is at the heart of Philip K. Dick's groundbreaking novel, the first book in his defining trilogy. When a beam of pink light begins giving a schizophrenic man named Horselover Fat (who just might also be known as Philip K. Dick) visions of an alternate Earth where the Roman Empire still reigns, he must decide whether he is crazy or whether a godlike entity is showing him the true nature of the world.

In the year 2475, the remnants of humanity have taken to the skies, inhabiting massive domed cities that hover five miles over the ruined ecological disaster of old Earth. The Powers That Be, in their infinite wisdom, decided that the few million people left deserved to live their best lives, so they gave each sub-orbital platform its own theme and legally enforced tech level.

The Ultimate Science Fiction Mega Collection contains 24 of the greatest science-fiction works ever written.