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The Receiver: A Hard Sci-Fi First Contact Techno-Thriller Best Value The Receiver: A Hard Sci-Fi First Contact Techno-Thriller 
The Silent Colony: A Hard Science Fiction Novel of First Contact and Ancient Secrets The Silent Colony: A Hard Science Fiction Novel of First Contact and Ancient Secrets 
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A Military Hard Science Fiction Epic (Aeon 14: The Sol Dissolution Book 1) The Wooden Pen Press Venusian Uprising - A Military Hard Science Fiction Epic (Aeon 14: The Sol Dissolution Book 1) Mozaika Publications Oasis (The Last Humans Book 1) J Triptych Publishing The Piranha Solution: A Hard Sci Fi Technothriller (Ace of Space Book 1) J Triptych Publishing The Piranha Solution: A Hard Sci Fi Technothriller (Ace of Space Book 1) scifi-thriller.com Reactor: Science Fiction Thriller scifi-thriller.com Reactor: Science Fiction Thriller Hard-SF.com Mars Nation 1: Hard Science Fiction (Mars Trilogy) Hard-SF.com Mars Nation 1: Hard Science Fiction (Mars Trilogy) Audible The Prefect Audible The Prefect Hard-SF.com The Luna Monolith: Hard Science Fiction (The Black Monolith Book 1) Hard-SF.com The Luna Monolith: Hard Science Fiction (The Black Monolith Book 1) Hard-SF.com The Atacama Incident: Hard Science Fiction Hard-SF.com The Atacama Incident: Hard Science Fiction AS1 AS1 The Shackleton Signal: Hard SF Thriller The Shackleton Signal: Hard SF Thriller Harper Voyager Onward, Voyager: A Collection of Teasers of Bestselling Science Fiction and Fantasy Novels by Harper Voyager Nexus: A Science-Fiction Thriller Nexus: A Science-Fiction Thriller Futureword Publishing Blue SunRise: A Riveting Character-driven Hard Sci-fi Adventure (Blue Sun Space Opera Book 1) Futureword Publishing Blue SunRise: A Riveting Character-driven Hard Sci-fi Adventure (Blue Sun Space Opera Book 1) Green Hill Publishing Homo Machina: A Post-Apocalyptic Hard Sci-fi Genetic Engineering Thriller Green Hill Publishing Homo Machina: A Post-Apocalyptic Hard Sci-fi Genetic Engineering Thriller Edenroot Press Deep Space Expedition: A Hard Science Fiction Survival Mission (The Threshold Protocol Book 1) Edenroot Press Deep Space Expedition: A Hard Science Fiction Survival Mission (The Threshold Protocol Book 1) Hard-SF.com Proxima Rising: Hard Science Fiction (Proxima Trilogy Book 1) Hard-SF.com Proxima Rising: Hard Science Fiction (Proxima Trilogy Book 1) Exodus Protocol: Exodus Protocol: A Hard Military Science Fiction Thriller Exodus Protocol: Exodus Protocol: A Hard Military Science Fiction Thriller Hard-SF.com The Hole: Hard Science Fiction (Solar System Series Book 1) Hard-SF.com The Hole: Hard Science Fiction (Solar System Series Book 1) Endeavour (A Sleeping Gods Novel Book 1) Endeavour (A Sleeping Gods Novel Book 1) The Mars Anomaly: Hard Science Fiction The Mars Anomaly: Hard Science Fiction Quartermaster Press Darwin's Dilemma: A Metaphysical Hard Sci-fi AI Technothriller Quartermaster Press Darwin's Dilemma: A Metaphysical Hard Sci-fi AI Technothriller Florida Gone: A Hard Science Fiction Novel of Time Collapse, Climate Catastrophe, and Survival in Earth’s Prehistoric Pa Florida Gone: A Hard Science Fiction Novel of Time Collapse, Climate Catastrophe, and Survival in Earth’s Prehistoric Pa J Triptych Publishing Visitor: A Hard Sci Fi Thriller (Transcendence Book 1) J Triptych Publishing Visitor: A Hard Sci Fi Thriller (Transcendence Book 1) Hard-SF.com The Torn Planet: Hard Science Fiction (The Marchenko Logfiles Book 1) Hard-SF.com The Torn Planet: Hard Science Fiction (The Marchenko Logfiles Book 1) Hard-SF.com The Clouds of Venus: Hard Science Fiction (Solar System Series Book 5) Hard-SF.com The Clouds of Venus: Hard Science Fiction (Solar System Series Book 5)