It was a very good guess. Also, kind of right, but really more not?

"We just called it 'the ground'," Octavia replied, with a hint of a dry drawl about her tone. "But the short version is that it's this planet, just one nuclear apocalypse and a hundred and fifty years or so later."

She was yet to figure out just how close they were geographically to where she'd been living before she got yanked to the island, too.