Probability Sun (The Probability Trilogy Book 2)

Name: Probability Sun (The Probability Trilogy Book 2)
Price: 3.99 USD
Availability: InStock
Rating: 4.2 (110 reviews)
Author: Nancy Kress

by Nancy Kress

Thriller Science Fiction

4.2 (110)

4.2 stars from 110 reviews

348 pages~5.8 hr readPublished by TorPublished 2001-01-01

$3.99Deal73% off peak

Last checked: Jul 3, 2026

Price history: $1.99 – $14.99

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Price range: $1.99 – $14.99

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Fans of these books will like this...

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Perfect for you if...

You love hard sci-fi that treats physics and alien technology as genuinely strange and dangerous, not just window dressing.
You're drawn to stories where the stakes are civilisational and every decision could reshape human survival.
You appreciate ensemble casts where multiple perspectives on the same crisis reveal different truths.

Maybe not for you if...

You need standalone novels. This is book two of a trilogy and assumes you know the established conflict with the Fallers.
You prefer character-driven narratives over conceptual exploration. The ideas here matter more than intimate emotional arcs.
You want clear answers. Kress leaves genuine ambiguity about whether the artifact is salvation or doom.

About this book

Humanity faces extinction in a war against the Fallers, an alien race committed to genocide. The discovery of a strange artifact on a distant planet may offer a path to survival. The artifact functions as both a powerful weapon and potentially a key to understanding a lost superscience—one the Fallers may have already unlocked. However, the artifact carries another possibility: it could be a doomsday machine capable of destroying the fabric of space itself. Humanity must determine whether this discovery represents salvation or annihilation.

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Price History

Kindle price over time. Green zones = periods when the book was free.

$1.99 – $14.99

Currently on sale at $3.99 — 73% off peak. Price has dropped 4 times over the last 6 years. Goes on sale roughly every 75 days. Typically stays discounted for 1 day.

Sales Rank

Amazon sales rank: lower number = better selling book. #1 is the bestseller.

Currently around #18K in the Kindle store — a steady mid-list seller.

Rating & Reviews

Purple line = star rating over time. Blue area = total review count growth.

Currently 4.2★ from 110 reviews

Gaining approximately 1 new review per month. Rating has climbed from 4.1 to 4.2. Recent readers are rating it higher.

Sale Prediction

Actual Predicted

This book is currently discounted at $3.99. It typically returns to around $14.99.

Prices shown in USD from Amazon US. We continuously pull new data to improve tracking. If dates look old, it usually means there has been no significant change since the last data point.