A geologist with an extensive knowledge of crystals, Lyra Erso helped her husband Galen with his work before he became involved with Orson Krennic’s energy-enrichment project. Deeply suspicious of both Krennic and the Empire, Lyra believed in the Force and tried to share her faith with her daughter Jyn. When Krennic tracks the Ersos to Lah’mu, she risks everything to protect her family.
A small desert moon frosted by a permanent winter, Jedha is home to one of the first civilizations to explore the nature of the Force. At one time a world important to the Jedi Order, Jedha serves as a holy site for pilgrims from across the galaxy who seek spiritual guidance. Now, the Empire occupies Jedha, and a prolonged battle between Imperial forces and scattered Rebels carries on in the timeworn streets.
At the heart of every Jedi lightsaber is a kyber crystal found on several planets, most notably the icebound caves of Ilum. This crystal is attuned to the Force, and connected to a Jedi Knight on a deeply personal level. In this way, a lightsaber is an extension of a Jedi's Force awareness. Because Jedi let the Force guide their selection of the crystal, the vibration that the crystal creates in the lightsaber blade helps Jedi center themselves and find balance in the Force. In this way, a Jedi can center his or her attention beyond the distractions of combat. A lightsaber crystal is colorless until first attuned and connected to a Jedi -- at which times it glows either blue or green, or in some rare instances, another shade. From that point on, it retains that hue.