Past Kindle Book Deals but Still Must Read Books!
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These Books Earned Our Seal of Approval—Snag Them Before They Vanish (Again)
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125 past books matching Hard Sci-Fi
A strong match for readers who enjoy hard science fiction, space missions, and planetary disaster scenarios.
The Hammer of God
Sci-Fi · Hard Sci-Fi · Space Exploration
Our take
Called “Entertaining . . . [Clark] handles both ideas and characters with deftness and wit” by the Chicago Sun-Times, this science fiction thriller takes place a century into the future, when a massive asteroid named Kali threatens to destroy all life on Earth. As scientists race to prevent disaster, Captain Robert Singh aboard the starship Goliath may be humanity’s only hope, though stopping the asteroid could require the ultimate sacrifice. A strong match for readers who enjoy hard science fiction, space missions, and planetary disaster scenarios.
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About the book
From one of the bestselling science fiction authors of all time comes this heart-stopping far future novel of an asteroid on a collision course with Earth.
A century into the future, technology has solved most of the problems that have plagued our time. However, a new problem is on the horizon—one greater than humanity has ever faced. A massive asteroid is racing toward Earth, and its impact could destroy all life on the planet.
Immediately after the asteroid—named "Kali" after the Hindu goddess of chaos and destruction—is discovered, the world's greatest scientists begin researching a way to prevent the disaster. In the meantime, Cpt. Robert Singh, aboard the starship Goliath, may be the only person who can stop the asteroid. But this heroic role may demand the ultimate sacrifice.
"Entertaining . . . [Clark] handles both ideas and characters with deftness and wit." —Chicago Sun-Times
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A strong match for readers drawn to first-contact science fiction mixed with mystery, investigation, and deep-space exploration.
Infinity Beach
Sci-Fi · Hard Sci-Fi · Space Colonization · Space Opera
Our take
Called “masterly” by Library Journal, Infinity Beach follows Dr. Kimberly Brandywine as she investigates the disappearance of her clone-sister after a failed SETI expedition and discovers that the ship’s log was falsified. A strong match for readers drawn to first-contact science fiction mixed with mystery, investigation, and deep-space exploration.
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About the book
Nebula-winning author of the Alex Benedict series:A woman steals a starship to find her long-lost clone-sister in a "masterly" novel of first contact (Library Journal).
We are alone. That is the verdict, after centuries of Search for Extra-Terrestrial Intelligence missions and space exploration. The only living things in the Universe are found on the Nine Worlds settled from Earth, and the starships that knit them together. Or so it's believed, until Dr. Kimberly Brandywine sets out to find what happened to her clone-sister Emily, who, after the final unsuccessful manned SETI expedition, disappeared along with the rest of her ship's crew.
Following a few ominous clues, Kim discovers the ship's log was faked. Something happened out there in the darkness between the stars, and she's prepared to go to any length to find answers. Even if it means giving up her career . . . stealing a starship . . . losing her lover. Kim is about to discover the truth about her sister—and about more than she ever dared imagine.
"Gripping mystery . . . an altogether splendid, satisfying puzzle." —Kirkus Reviews
"Will hold readers in thrall." —Publishers Weekly (starred review)
"Exquisitely timed revelations maximize suspense . . . fine characterization and world building." —Booklist
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A strong match for readers drawn to character-centered space opera, political maneuvering, family ambition, and contested artifacts.
Provenance
LGBTQIA+ · Sci-Fi · Hard Sci-Fi
Our take
Ingray frees a thief from a prison planet in hopes of recovering her family’s priceless artifacts and improving her chances of becoming heir, only to return home to political turmoil and an escalating interstellar conflict, with a 4.0-star average from more than 500 Goodreads ratings. A strong match for readers drawn to character-centered space opera, political maneuvering, family ambition, and contested artifacts.
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About the book
An ambitious young woman has just one chance to secure her future and reclaim her family's priceless lost artifacts in this stand-alone novel set in the world of the award-winning, New York Times bestselling Imperial Radch trilogy.
Though she knows her brother holds her mother's favor, Ingrid is determined to at least be considered as heir to the family name. She hatches an audacious plan -- free a thief from a prison planet from which no one has ever returned, and use them to help steal back a priceless artifact.
But Ingray and her charge return to her home to find their planet in political turmoil, at the heart of an escalating interstellar conflict. Together, they must make a new plan to salvage Ingray's future and her world, before they are lost to her for good.
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Ideal for readers looking for interstellar travel, coming-of-age fiction, romance, and large-scale disaster.
Variable Star
Sci-Fi · Hard Sci-Fi · Space Opera
Our take
Called “a delight” by David Crosby, this science fiction novel follows aspiring composer Joel Johnston as he rejects the future planned by his wealthy fiancée’s family and leaves aboard a colony ship, only for a cosmic catastrophe to threaten humanity, with a 4.0-star rating from more than 70 Amazon reviewers. Ideal for readers looking for interstellar travel, coming-of-age fiction, romance, and large-scale disaster.
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About the book
The unfinished sci-fi masterpiece by the author of Stranger in a Strange Land—completed by the Hugo Award–winning author of The Stardance Trilogy.
Joel Johnston has found the love of his life in Jinny Hamilton. Life would be perfect if only he earned enough money to support a family. But now that Jinny knows his love is true, she reveals an incredible secret: she is really Jinny Conrad, granddaughter of Richard Conrad, the wealthiest man in the solar system. And now that Joel proven his love for Jinny, her family has a plan for him.
Joel is to be groomed for a place in the vast Conrad empire and sire a dynasty to carry on the family business. Most men would jump at the opportunity. But to Jinny's surprise, and even his own, Joel turns down her generous offer and sets off on the mother of all benders.
When he wakes up on a colony ship heading into space, he decides it's time to forget Jinny and make a life among the stars. But his plans—and the plans of billions of others—are shattered by a cosmic cataclysm so devastating it will take all of humanity's strength and ingenuity just to survive.
When an outline for Variable Star was found among Robert A. Heinlein's papers, Spider Robinson was commissioned to complete the novel. The result is a thrilling new work of science fiction from two of the genre's greatest minds.
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Best for readers who like hard science fiction, vintage computers, scientific mysteries, and high-stakes technology.
Retro Fold
Sci-Fi · Hard Sci-Fi · Time Travel
Our take
Fourteen-year-old prodigy Ethan Cole buys an old Apple II and discovers the vanished research of a Cold War physicist whose unsanctioned project could reshape modern physics. With decades of technological progress now making the work possible, Ethan must decide whether to finish what the missing scientist started. Best for readers who like hard science fiction, vintage computers, scientific mysteries, and high-stakes technology.
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About the book
At the end of the Cold War, a physicist at Oak Ridge National Laboratory was pursuing an unsanctioned project that could reshape modern physics. Then he vanished — his lab seized, his research classified, his name erased from the record.
Thirty-five years later, Ethan Cole — fourteen years old, a prodigy, more capable than engineers twice his age — purchases the physicist's old Apple II at an estate sale. Inside, he finds hand-built hardware, encrypted disks, and notebooks full of equations thought to have disappeared with the physicist. The work was revolutionary and ahead of its time. Decades ahead.
Fully realizing the physicist's vision wasn't possible with 1980s technology. But three decades of advancement have closed the gap — and Ethan has the skills to finish what was started. The question is whether he should. The last person who tried never came home.
Sometimes going back is the only way forward.
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Good for readers who want idea-driven sci-fi with alien mysteries, high-stakes discovery, and questions about humanity’s place in the universe.
Frequency 2
Sci-Fi · First Contact · Hard Sci-Fi · Techno-Thriller
Our take
From multimillion-copy international bestselling authors Douglas E. Richards and Joshua T. Calvert, Frequency 2 follows parallel missions from Patagonia to Europa as strange signals, synchronized brainwaves, and an alien rescue push humanity toward a new understanding of consciousness and first contact. Good for readers who want idea-driven sci-fi with alien mysteries, high-stakes discovery, and questions about humanity’s place in the universe.
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About the book
A desperate race to revive an alien buried on an icy moon. A fringe cult tuned into signals from the stars. And two extraordinary women willing to risk everything to forge humanity’s destiny.
The second and final entry in the electrifying series from multimillion-copy international bestselling authors Douglas E. Richards and Joshua T. Calvert.
Four years after the world-changing events of Frequency, the fragile hope born on Europa has fractured under cults, conspiracy theories, and misread alien wisdom. When a remote group in Patagonia begins displaying synchronized brainwave patterns that match nothing on Earth, Alexandra and Ethan Calloway race to investigate. What they find is astonishing: signals from a distant star system channeled through something hidden in the Patagonian wilderness—something that shouldn’t exist.
On Jupiter’s frozen moon, Milo Daven and Elena Vasquez lead a desperate mission to reach the alien whose message changed the world. In an environment that makes Antarctica seem like paradise, they’ll attempt the unthinkable: a rescue that could rewrite humanity’s place in the universe.
As parallel threads of discovery converge, Alexandra, Elena, and their teams confront questions that push the boundaries of science, consciousness, and the interconnectedness of all things. Are we ready for what comes next?
A mind-bending journey into hidden frequencies that bind minds across worlds, Frequency 2 delivers the jaw-dropping payoff to one of the most visionary first-contact series ever written.
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A strong match for readers drawn to hard science fiction, outbreak stories, genetic engineering, political tension, and near-future dystopian stakes.
Immunity Index
Dystopian · Genetic Engineering · Hard Sci-Fi
Our take
An Amazon Best of the Month pick, Immunity Index follows three young women in a near-future US shaped by food shortages, inequality, and authoritarian rule as they discover their shared genetic origins while a deadly virus spreads, with a 4.1-star rating from more than 100 Amazon reviewers. A strong match for readers drawn to hard science fiction, outbreak stories, genetic engineering, political tension, and near-future dystopian stakes.
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About the book
Sue Burke, author of Semiosis and Interference, gives readers a new near-future, hard sf novel. Immunity Index blends Orphan Black with Contagion in a terrifying outbreak scenario.
Bustle's 40 Best New Books May 2021
Amazon Best of the Month May 2021
In a US facing growing food shortages, stark inequality, and a growing fascist government, three perfectly normal young women are about to find out that they share a great deal in common.
Their creator, the gifted geneticist Peng, made them that way—before such things were outlawed.
Rumors of a virus make their way through an unprotected population on the verge of rebellion, only to have it turn deadly.
As the women fight to stay alive and help, Peng races to find a cure—and the cover up behind the virus.
At the Publisher's request, this title is being sold without Digital Rights Management Software (DRM) applied.
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Best for readers who like idea-driven hard science fiction with ringworld settings, far-future technology, space opera scale, and competing realities.
Lady of Mazes
Sci-Fi · Hard Sci-Fi · Space Opera
Our take
“hard SF at its best” by Stephen Baxter, Lady of Mazes follows Livia Kodaly as she becomes Teven Coronal’s only hope against human and superhuman invaders threatening its fragile ecologies and many human civilizations, with a 4.1-star rating from more than 100 Amazon reviewers. Best for readers who like idea-driven hard science fiction with ringworld settings, far-future technology, space opera scale, and competing realities.
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About the book
"This is hard SF at its best. . . Schroeder belongs to a dynasty that includes Benford, Vinge and Egan." —Stephen Baxter
Author and professional futurist Karl Schroeder, whose novels Ventus and Permanence have established him as a groundbreaking visionary in hard science fiction, extends his imagination into Larry Niven territory, returning to the same distant future in which Ventus was set, but employing a broader canvas, to tell the story of Teven Coronal, a ringworld with a huge multiplicity of human civilizations.
Brilliant but troubled Livia Kodaly is Teven's only hope against invaders both human and superhuman who would destroy its fragile ecologies and human diversity.
Filled with action, ideas, and intellectual energy, Lady of Mazes is the hard SF novel of the year.
"With Lady of Mazes, Schroeder gives us another novel of marvelous insight—brightest glimpses of where our technology of communication and computation may be taking us." —Vernor Vinge
"A complete original . . . it's the most thought-provoking and interesting work of hard SF that I've read in the past year, and it deserves to be recognized as belonging to the cutting edge of the new far future in SF." —Charles Stross
"An astonishing saga. One helluva read!" —Charles Harness
"Karl Schroeder has always had a knack for intelligent and provocative thought experiments, disguised as space opera. Now he ups the ante with a fascinating riff on consensual (and conflicting) realities. Lady of Mazes contains more cool ideas than Ventus and Permanence combined." —Peter Watts
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A strong match for readers drawn to hard science fiction about first contact, space exploration, and life beyond Earth.
The Sunborn
Dystopian · Hard Sci-Fi
Our take
The Sunborn follows the mystery of marsmat, a complex life-form discovered beneath the surface of Mars, as the search for answers carries humanity beyond Pluto, with a 4.3-star rating from more than 60 Amazon reviewers. A strong match for readers drawn to hard science fiction about first contact, space exploration, and life beyond Earth.
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About the book
The multiple award-winning author of Timescape and Eater, Gregory Benford returns with a gripping new novel set in the same dynamic future as his wildly popular The Martian Race.
The first manned mission to Mars has been successful. However, there is a gathering mystery surrounding "marsmat"- the complex, anaerobic life-form that the expedition discovered inside a honeycomb of tunnels below the planet's surface. The search for the answers to humanity's ultimate questions about life in the universe will lead to the fringes of the solar system-to the dark and cold void beyond the planet Pluto.
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Good for readers who like hard science fiction about evolution, epidemiology, government cover-ups, and human survival.
Darwin’s Radio
Sci-Fi · Genetic Engineering · Hard Sci-Fi
Our take
Nebula Award winner and Hugo Award finalist Darwin’s Radio is a Hugo Award nominee about a prehistoric disease reawakening in human DNA, as scientists race to solve the mystery behind a deadly epidemic targeting pregnant women, with a 4.2-star rating from more than 1,100 Amazon reviewers. Good for readers who like hard science fiction about evolution, epidemiology, government cover-ups, and human survival.
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About the book
HUGO AWARD FINALIST • “WOW! What a splendid (scary) notion: a human upgrade! What a superb plot! Darwin's Radio is bloody damned good.”—Anne McCaffrey
“Virus hunter” Christopher Dicken is a man on a mission, following a trail of rumors, government cover-ups, and dead bodies around the globe in search of a mysterious disease that strikes only pregnant women and invariably results in miscarriage. But when Dicken finds what he’s looking for, the answer proves to be stranger—and far deadlier—than he ever could have imagined. Something that has slept in human DNA for millions of years is waking up.
Molecular biologist Kaye Lang has spent her career tracing ancient retroviruses in the human genome. She believes these microscopic fossils can come to life again. But when Dicken’s discovery becomes public, Lang’s theory suddenly turns to chilling fact. As the outbreak of this terrifying disease threatens to become a deadly epidemic, Dicken and Lang must race against time to assemble the pieces of a puzzle only they are equipped to solve—an evolutionary puzzle that will determine the future of the human race . . . if a future exists at all.
Praise for Darwin’s Radio
“Bear is one of our very best, and most innovative, speculative writers.”—New York Daily News
“Superb . . . Bear's novel is frighteningly believable with a lot of clearly explained hard science, but the personal struggles of the well-realized characters keep everything on a human level.”—Focus
“Bear is a writer of passionate vision.”—Locus
“Darwin’s Radio scores a high rating on the thrill monitor.”—Birmingham Post (England)
“Absorbing and ingenious.”—Kirkus Reviews
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Good for readers who like biopunk science fiction, genetic engineering, strange futures, and dangerous new species.
Fairyland
Dystopian · Sci-Fi · Hard Sci-Fi
Our take
In a post-Millennium world of ecological collapse, gene-hacker Alex Sharkey helps a genetically enhanced genius child transform compliant blue-skinned dolls into self-aware fairies, with a 4.0-star rating from more than 200 Amazon reviewers. Good for readers who like biopunk science fiction, genetic engineering, strange futures, and dangerous new species.
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About the book
"McAuley gives us a vision ..." - Matthew Cheney
"...one of Paul J. McAuley's greatest works in fantasy and science fiction, demonstrating his great gifts in storytelling and writing" - Goodreads Reviewer
Alex Sharkey is trying to make his mark as a biohacker - a designer of rare psychoactive viruses - and stay one step ahead of the law. After meeting a scary, super-smart little girl called Milena his troubles really start. Together they quicken the intelligence in a Doll - a being genetically-engineered for slave labour - accidentally creating a new species and turning it into the first of the fairies.
Milena isn't sure if she's mad or if she's the only sane person left in the world; she only knows that she wants to escape to her own private Fairyland and live forever. But some of the Folk, as dangerous as any in legend, have other ideas about her destiny...
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Good for readers who want science fiction about AI, robotics, secrecy, and human identity.
The Phoenix Code
Sci-Fi · Hard Sci-Fi · Space Opera
Our take
“Continues to dazzle us with brilliance in combining science, romance and adventure” Romantic Times, The Phoenix Code follows MIT professor Megan O’Flannery as she works with a secret android named Ander, loosening his controls until independent thought turns dangerous, with a 4.2-star rating from more than 160 Amazon reviewers. Good for readers who want science fiction about AI, robotics, secrecy, and human identity.
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About the book
The Nebula Award–winning author "continues to dazzle us with brilliance in combining science, romance and adventure." —Romantic Times
MIT professor Megan O'Flannery is one of the world's leading research scientists on artificial intelligence for androids. Most of her work consists of working with computer simulations, so when the company MindSim gives Megan an opportunity to work with an android, she jumps at the chance.
Hidden and secret, an underground compound in the Nevada desert offers Megan a spectacular lab where she can live and work, mostly alone except for robotic assistants—and the android. Although it appears physically indistinguishable from a human man, Megan realizes she has a lot of work ahead if he is ever to think and act like a human, let alone the superspy that MindSim wants him to be. She loosens the controls on his behavior, allowing the android—who soon chooses the name Ander—the freedom of more independent thought.
However, when Raj Sundaram, the reclusive genius of robotics, arrives at the compound to work with the android, Ander's behavior takes a strange turn, causing Megan to distrust Raj. As Ander's development spins out of control, he throws the project into chaos, going rogue even as he becomes stronger—and more dangerously human.
"This novel is clearly science fiction first with a dynamic climax that will stun the unsuspecting audience who will fail to break The Phoenix Code before Ms. Asaro reveals the ending of this keeper." —Painted Rock Reviews
"Cinematic energy and the ease and confidence of a seasoned bestseller." —SFReviews.net
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