Inconstant Moon is a collection of science fiction short stories by acclaimed American author Larry Niven, originally published in 1973. The stories span a range of science fiction subgenres and showcase Niven’s skill at crafting thought-provoking tales that blend hard science with imaginative premises. While some of the stories are set in Niven’s well-known “Known Space” universe, others take place in entirely different worlds or even our own contemporary reality viewed through a science fictional lens.
The Title Story
The collection takes its name from the Hugo Award-winning title story “Inconstant Moon”, first published in the 1971 anthology All the Myriad Ways. In this suspenseful tale set in then-present day Los Angeles, a man named Stan notices one night that the moon is glowing far brighter than normal. Realizing this likely means that the sun has gone nova, Stan grapples with the end of the world being mere hours away once the Earth rotates into the oncoming destructive solar waves.
Stan decides to spend his final hours rekindling his relationship with Leslie, a woman he has known for years. In a series of poignant scenes, they share their last night on Earth together, reacting to the impending apocalypse in different ways. Stan initially keeps his suspicions about the nova to himself, not wanting to alarm Leslie, but is surprised to discover that she independently figured out the situation as well.
Niven masterfully builds tension and emotion as the characters process their fate and decide how to spend their remaining time. But a twist in the final act reveals that the sun has not gone nova after all – Earth has instead been hit by a massive solar flare. While still a cataclysmic disaster, this “inconstant moon” at least means a chance of survival for those on the night side of the planet. Stan and Leslie then shift gears into working to secure shelter and supplies to make it through the aftermath.
The story is a prime example of Niven’s ability to use a science fictional premise to explore very human themes. The pending apocalypse strips away the characters’ inhibitions and hangups, allowing them to connect authentically and reveal their true priorities and feelings for each other. At the same time, Niven grounds the scenario in plausible astronomy and physics, making the threat feel visceral and immediate. It’s a masterful blend of romance, suspense, and scientific speculation.
Inconstant Moon on Screen
The enduring appeal of “Inconstant Moon” is evidenced by the fact that it was adapted into an episode of the 1990s revival of The Outer Limits television series. The 1996 episode, scripted by Brad Wright, stays fairly faithful to Niven’s story, though it fleshes out the characters of Stan and Leslie a bit more, portraying them as a nerdy astronomy professor and a bookstore owner who have had an on-again/off-again flirtation over the years.
The TV version builds out both the romantic and apocalyptic elements, with suitably moody cinematography selling the eerie moonlight and some impressively staged disaster sequences as the solar flare’s effects begin to be felt. Like the short story, it manages to tell a satisfying self-contained tale while leaving the ultimate fate of the world and the protagonists intriguingly ambiguous. It’s a worthy adaptation of one of Niven’s most famous works.
Other Notable Stories
While “Inconstant Moon” is the clear standout, the rest of the collection also has much to offer. “Bordered in Black” is another tale with an astronomical theme, featuring an astronaut who discovers a mysterious black border surrounding an alien planet. As he investigates, the border’s true nature proves to have unsettling implications for the nature of the universe. It’s a clever concept with a brain-bending payoff.
“One Face” sees Niven returning to the subgenre of far future “dying Earth” stories. When a spacecraft emerges from a hyperspace jump gone wrong, its crew finds themselves in a solar system where billions of years have passed, the sun has become a white dwarf, and Earth’s atmosphere has frozen onto its dark side. The story follows the difficult choices the crew must make to survive in this bleak environment. It’s a pensive, almost elegiac take on the deep time implications of astronomy.
Not all the stories reach the same heights. “Death by Ecstasy” aims to be a murder mystery with a science fictional twist, but the plot feels a bit thin. “The Jigsaw Man” is a darkly satirical take on organ harvesting and the justice system that comes across as more cynical and mean-spirited than Niven’s usual style. But even the less effective entries still showcase Niven’s lively imagination and gift for high concept premises.
Niven’s Strengths
Throughout Inconstant Moon, Niven plays to his strengths of rigorous extrapolation from scientific principles and an ability to make the cosmic feel personal and relatable. His prose style is straightforward and no-nonsense, always in service of clearly communicating the ideas at the core of each story. But he balances the exposition and theoretical speculation with enough human drama to keep things emotionally grounded.
This collection also benefits from Niven’s sheer breadth of subject matter and subgenre. From near future thrillers to far future epics, from alien worlds to altered versions of our own, Niven seems determined to explore every corner of the science fiction landscape. But whether he’s dealing with astrophysics, biology, sociology, or speculative technology, his stories always circle back to the human element and how we react when confronted with the unknown and the extraordinary.
Summary
Inconstant Moon may not be the ideal entry point for those unfamiliar with Niven’s writing, as it lacks a unifying theme or setting beyond simply being a showcase of the author’s range. Those are perhaps better off starting with one of his “Known Space” collections or the novel Ringworld to get a fuller sense of the intricate future history he crafted.
But for established fans or those who appreciate science fiction short stories in general, Inconstant Moon is well worth seeking out. It’s a strong sampler of one of the field’s most celebrated authors, demonstrating both his bold ideas and his ability to use those ideas in service of involving, human-scale storytelling. Like the astronomical event that gives the collection its title, Inconstant Moon shines brightly and illuminates our perspective on the universe around us.
