This lore can be found on Tython.
The birthplace of the Jedi Order was lost for many thousands of years when known hyperspace lanes leading to the region collapsed–a fate that has befallen many worlds in the unstable heart of the galaxy known as the Deep Core. After the destruction of the Jedi Temple on Coruscant, Satele Shan embarked on a search to rediscover the lost world. Guided by the Force, she ventured into the Deep Core and re-emerged with astrogation charts detailing a new series of stable hyperspace lanes. Tython was once again connected to the rest of the galaxy. Initial exploration of the planet took months, as Jedi scouts combed the surface for clues to Tython’s history. Lives were lost–to a troubled landscape, to the Flesh Raiders and to forces unknown–but soon, the Jedi Council established a new temple on the world, determined to rebuild Tython and return it to humble glory.