Ringworld


Larry Niven - 1970
    Pierson's puppeteers, the aliens who discovered it, are understandably wary of encountering the builders of such an immense structure and have assembled a team of two humans, a mad puppeteer and a kzin, a huge cat-like alien, to explore it. But a crash landing on the vast edifice forces the crew on a desperate and dangerous trek across the Ringworld.

The Gods Themselves


Isaac Asimov - 1972
    But even free energy has a price. The transference process itself will eventually lead to the destruction of the Earth's Sun--and of Earth itself.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.

Gateway


Frederik Pohl - 1977
    and on reaches of unimaginable horror. When prospector Robinette Broadhead went out to Gateway on the Heechee spacecraft, he decided he would know which was the right mission to make him his fortune. Three missions later, now famous and permanently rich, Rob Broadhead has to face what happened to him and what he has become... in a journey into himself as perilous and even more horrifying than the nightmare trip through the interstellar void that he drove himself to take!

The Forever War


Joe Haldeman - 1974
    A reluctant conscript drafted into an elite Military unit, Private William Mandella has been propelled through space and time to fight in the distant thousand-year conflict; to perform his duties without rancor and even rise up through military ranks. Pvt. Mandella is willing to do whatever it takes to survive the ordeal and return home. But "home" may be even more terrifying than battle, because, thanks to the time dilation caused by space travel, Mandella is aging months while the Earth he left behind is aging centuries.

A Fire Upon the Deep


Vernor Vinge - 1992
    A Fire upon the Deep is the big, breakout book that fulfills the promise of Vinge's career to date: a gripping tale of galactic war told on a cosmic scale.Thousands of years hence, many races inhabit a universe where a mind's potential is determined by its location in space, from superintelligent entities in the Transcend, to the limited minds of the Unthinking Depths, where only simple creatures and technology can function. Nobody knows what strange force partitioned space into these "regions of thought," but when the warring Straumli realm use an ancient Transcendent artifact as a weapon, they unwittingly unleash an awesome power that destroys thousands of worlds and enslaves all natural and artificial intelligence.Fleeing the threat, a family of scientists, including two children, are taken captive by the Tines, an alien race with a harsh medieval culture, and used as pawns in a ruthless power struggle. A rescue mission, not entirely composed of humans, must rescue the children-and a secret that may save the rest of interstellar civilization.

Red Mars


Kim Stanley Robinson - 1992
    For centuries, Mars has beckoned humans to conquer its hostile climate. Now, in 2026, a group of 100 colonists is about to fulfill that destiny.John Boone, Maya Toitavna, Frank Chalmers & Arkady Bogdanov lead a terraforming mission. For some, Mars will become a passion driving them to daring acts of courage & madness. For others it offers an opportunity to strip the planet of its riches. For the genetic alchemists, it presents a chance to create a biomedical miracle, a breakthrough that could change all we know about life & death. The colonists orbit giant satellite mirrors to reflect light to the surface. Black dust sprinkled on the polar caps will capture warmth. Massive tunnels, kilometers deep, will be drilled into the mantle to create stupendous vents of hot gases. Against this backdrop of epic upheaval, rivalries, loves & friendships will form & fall to pieces--for there are those who will fight to the death to prevent Mars from ever being changed.Brilliantly imagined, breathtaking in scope & ingenuity, Red Mars is an epic scientific saga, chronicling the next step in evolution, creating a world in its entirety. It shows a future, with both glory & tarnish, that awes with complexity & inspires with vision.

Starship Troopers


Robert A. Heinlein - 1959
    We just call it “The Bug War." Everything up to then and still later were "incidents," "patrols," or "police actions." However, you are just as dead if you buy the farm in an "incident" as you are if you buy it in a declared war...In one of Robert A. Heinlein’s most controversial bestsellers, a recruit of the future goes through the toughest boot camp in the Universe—and into battle with the Terran Mobile Infantry against mankind’s most alarming enemy.

Way Station


Clifford D. Simak - 1963
    But what his neighbors must never know is that, inside his unchanging house, he meets with a host of unimaginable friends from the farthest stars.More than a hundred years before, an alien named Ulysses had recruited Enoch as the keeper of Earth's only galactic transfer station. Now, as Enoch studies the progress of Earth and tends the tanks where the aliens appear, the charts he made indicate his world is doomed to destruction. His alien friends can only offer help that seems worse than the dreaded disaster. Then he discovers the horror that lies across the galaxy...

Chasm City


Alastair Reynolds - 2001
    Now, with the entire city corrupted -from the people to the very buildings they inhabit- only the most wretched sort of existence remains. For security operative Tanner Mirabel, it is the landscape of nightmares through which he searches for a low-life postmortal killer. But the stakes are raised when his search brings him face to face with a centuries-old atrocity that history would rather forget.

Hyperion


Dan Simmons - 1989
    There are those who worship it. There are those who fear it. And there are those who have vowed to destroy it. In the Valley of the Time Tombs, where huge, brooding structures move backward through time, the Shrike waits for them all. On the eve of Armageddon, with the entire galaxy at war, seven pilgrims set forth on a final voyage to Hyperion seeking the answers to the unsolved riddles of their lives. Each carries a desperate hope—and a terrible secret. And one may hold the fate of humanity in his hands.

Spin


Robert Charles Wilson - 2005
    They all flared into brilliance at once, then disappeared, replaced by a flat, empty black barrier. He and his best friends, Jason and Diane Lawton, had seen what became known as the Big Blackout. It would shape their lives.Life on Earth is about to get much, much stranger.

Lord of Light


Roger Zelazny - 1967
    On a colony planet, a band of men has gained control of technology, made themselves immortal, and now rule their world as the gods of the Hindu pantheon. Only one dares oppose them: he who was once Siddhartha and is now Mahasamatman. Binder of Demons, Lord of Light.

Eon


Greg Bear - 1985
    NASA, NATO, and the UN sent explorers to the asteroid's surface...and discovered marvels and mysteries to drive researchers mad.For the Stone was from space--but perhaps not our space; it came from the future-but perhaps not our future; and within the hollowed asteroid was Thistledown. The remains of a vanished civilization. A human--English, Russian, and Chinese-speaking--civilization. Seven vast chambers containing forests, lakes, rivers, hanging cities...And museums describing the Death; the catastrophic war that was about to occur; the horror and the long winter that would follow. But while scientists and politicians bickered about how to use the information to stop the Death, the Stone yielded a secret that made even Earth's survival pale into insignificance.

To Your Scattered Bodies Go


Philip José Farmer - 1971
    When famous adventurer Sir Richard Francis Burton dies, the last thing he expects to do is awaken naked on a foreign planet along the shores of a seemingly endless river. But that's where Burton and billions of other humans (plus a few nonhumans) find themselves as the epic Riverworld saga begins. It seems that all of Earthly humanity has been resurrected on the planet, each with an indestructible container that provides three meals a day, cigarettes, alcoholic beverages, a lighter, and the odd tube of lipstick. But why? And by whom? That's what Burton and a handful of fellow adventurers are determined to discover as they construct a boat and set out in search of the river's source, thought to be millions of miles away. Although there are many hardships during the journey--including an encounter with the infamous Hermann Goring--Burton's resolve to complete his quest is strengthened by a visit from the Mysterious Stranger, a being who claims to be a renegade within the very group that created the Riverworld. The stranger tells Burton that he must make it to the river's headwaters, along with a dozen others the Stranger has selected, to help stop an evil experiment at the end of which humanity will simply be allowed to die. --Craig E. Engler

The Left Hand of Darkness


Ursula K. Le Guin - 1969
    His goal is to facilitate Winter's inclusion in a growing intergalactic civilization. But to do so he must bridge the gulf between his own views and those of the completely dissimilar culture that he encounters.Embracing the aspects of psychology, society, and human emotion on an alien world, The Left Hand of Darkness stands as a landmark achievement in the annals of intellectual science fiction.