100,000,000,000,000 is a fictional year. Well, it might one day become an actual year, but ain't none of us gonna be around to see it. This year exists in the far, far future. Approximately 100 trillion years into the future, give or take a millennia. It represents the very end of time itself. This is when the universe as we know it waves goodbye and good riddance. The year 100,000,000,000,000 appeared on the science fiction television series Doctor Who. Characters from the show journeyed 100 trillion years into the future in the eleventh episode of series three of the revival series titled "Utopia".
The planet Malcassairo was one of the last known worlds existing in this time era. Its native species were called the Malmooth, and it was also one of the last human outposts in the galaxy.
The Tenth Doctor, Martha Jones, and Jack Harkness accidentally arrived in this era in the TARDIS. Even the Doctor was shocked, saying that such a time period was practically impossible.