The Long Winter was the twenty-year period in Orion history that followed the Atom War.

The detonation of alien nuclear weaponry on Botchok in the Atom War of 12,237 BCE (reference stardate -142/37) heavily damaged the planet and led to a nuclear winter. Radiation poisoning and starvation afflicted the survivors of the war. Botchok's population had plummeted to only 20% of what it had been before the Atom War.

The Long Winter officially came to an end in 12,217 BCE (reference stardate -142/17). During this time, the master races of the Orions all but abandoned Botchok, suspending proxy warfare and using their offworld supplies of slaves for breeding. They made no effort to help those on the planet, considering it a waste of resources as Orions were born merely to fight and die anyway. The reconstruction of Botchok would not begin for almost another thirty years, when the 22nd Rigel Conference in January, 12,189 BCE (stardate -141/8901) eventually permitted the importation of healthy Orion slaves to repopulate, clean up and rebuild. The Book of Tears was a compilation of accounts from both native and offworld Orions, telling of the carnage.

The planet would never fully recover from the nuclear holocaust, despite the terraforming efforts of the Accord of Namazz and the First Stage. (FASA RPG module: The Orions: Book of Common Knowledge)