- "I think I've found the perfect place. Remote. A bit desolate, but tranquil."
- ―Saw Gerrera to the Ersos, referring to Lah'mu
Lah'mu was a ringed agrarian planet in the Raioballo sector of the Outer Rim Territories. Its small population of settlers included the Erso family, who relocated to Lah'mu after the Clone Wars, and were ultimately tracked down by Director Orson Callan Krennic years later.
- "It looks unspoiled."
- ―Galen Walton Erso
Lah'mu was an inaccessible planet located in the Raioballo sector of the galaxy's Outer Rim Territories, far from major hyperspace routes. Its planetary rings were primarily silica formed from the remains of one of the planet's ancient moons, pulverized long before the Clone Wars. Lah'mu retained one other natural satellite.
The planet itself was lush and dark green in color, and its biosphere transformed iron into chlorophyll. The climate was rainy. The planet's crust, which split numerous times during its early geological life, was fertile and rich with minerals and soils brought to the surface during this turbulent period. Many of the minerals found within the soil, including zinc, chlorine, cobalt, nitrogen, and boron, rendered the groundwater unpleasant to drink, despite the presence of an abundant hydrosphere. Further, volcanic tephra contaminated the greenery. Part of the reason for the rainfall and high mineral content was due to heavy volcanic and geothermal activity, especially in the Eastern hemisphere.
Verdant and tranquil, Lah'mu's surface hosted mountain peaks and plateaus, including some volcanoes, black sand beaches, saline seas, geysers, and farmlands. Settlers lived on the western hemisphere, particularly around the fertile lowlands.
Lah'mu was named from a Neimoidian word meaning "prosperity." Early in its geographic life, Lah'mu's crust split numerous times, bringing minerals and soils to the surface that would later be farmed by the planet's sparse settlers. Initially hosting several moons, Lah'mu gained a planetary ring after one ancient satellite was pulverized, its remaining material pulled into orbit to form silica rings that cast shadows across the planet's surface. Volcanoes ejected tephra during this formative period, contaminating Lah'mu's natural greenery, forcing later settlers to carefully sift the soil.
During the last decades of the Galactic Republic, the Ministry of Economic Development encouraged citizens to relocate to worlds such as Lah'mu in the Outer Rim Territories, and offered incentives such as land parcels for the development of homesteads. Although the effort was mismanaged and saw many worlds either sparsely populated or abandoned, Lah'mu was deemed safe if otherwise forgotten.
As of 13 BBY, Lah'mu hosted fewer than five hundred settlers, occupying farmlands on the western hemisphere. Many of these individuals arrived on Lah'mu seeking to avoid war; among them were the Erso family, whose association with Orson Krennic during the Clone Wars forced them into hiding on the remote, inaccessible world. Galen and Lyra Erso chose to reside in a sixty-five hectare homestead on the planet's less popular eastern side, purchased with the assistance of Saw Gerrera. The Ersos grew crops and utilized Pretormin Environmental GX-8 water vaporators to distill water vapor from the air.
Unfortunately for the family, Director Krennic ultimately tracked them down, and arrived on Lah'mu to take Galen, Lyra, and their young daughter Jyn, with him to ensure the completion of his stalled Death Star project. Galen refused, and a brief firefight erupted in which Krennic was dealt a glancing blow and Lyra was shot dead. Krennic's death troopers burned the homestead and took Galen into custody, while Jyn fled to the black gulch beyond the former homestead's edge. There, she secreted herself in a shelter beneath a hidden hatch camouflaged by an artificial rock. She was later rescued by Gerrera.
Lah'mu was sparsely populated, home to under five hundred human settlers who lived on verdant, tranquil farmlands across the western hemisphere. Most of the population came to the planet to avoid the Clone Wars, through encouragement from the Republic Ministry of Economic Development. Part of the reason for this sparse settling was because Lah'mu was too far from hyperspace routes. The planet had no known indigenous intelligent life.
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- Master & Apprentice audiobook (Mentioned only)
- Catalyst: A Rogue One Novel (First appearance, simultaneous with Catalyst: A Rogue One Novel audiobook) (Appears in hologram)
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- Rebel Rising
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- Rogue One: A Star Wars Story
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- Star Wars: Rogue One: A Junior Novel
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- Rogue One Adaptation 4 (In flashback(s))
- Star Wars: Squadrons (Mentioned only)
- Star Wars: Rogue One: The Ultimate Visual Guide
- Star Wars Super Graphic: A Visual Guide to a Galaxy Far, Far Away
- Star Wars: Absolutely Everything You Need to Know, Updated and Expanded
- Forces of Destiny: Tales of Hope & Courage (Indirect mention only)
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- Star Wars: The Last Jedi: The Visual Dictionary
- Star Wars Helmet Collection 34 (Databank A-Z: Davish Krail–Kuat Drive Yards)
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- Star Wars Encyclopedia of Starfighters and Other Vehicles
- Solo: A Star Wars Story The Official Guide
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- Ultimate Star Wars, New Edition
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- Star Wars: The Rise of Skywalker: The Visual Dictionary
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