Golana was an inhabited planet in the Alpha Quadrant. This was the home of a Bajoran colony since the beginning of the 24th century. Archaeologists from the Bajoran Archaeological Institute were studying the ruins of a technologically advanced civilization that had gone extinct over two thousand years before.
In 2374, the O'Briens visited the planet again. After running off into a cave, Molly O'Brien discovered an active time portal from this lost civilization and fell in. The portal sent Molly three hundred years into the past, when the planet was uninhabited. She was recovered after having experienced 10 years all by herself, and returned a different person than she once was.
As she was unable to re-acclimate to her former life, her parents made the difficult decision to return her to Golana's past, where she was happy and safe. Fortunately, older Molly encountered young Molly again only moments after her fall and sent her younger self back to her family.