Utopian Engine

The Utopian Engine was a time manipulator designed to accelerate the life energy of people, planets and even stars, then channelling it through a trans-dimensional portal into the Eternium, thus replenishing that universe. The Eighth Doctor learned of its existence after arriving in the timeline that would result from its creation, which allowed him to go back in time and unwittingly disrupt its operation so that, instead of it aging everything on Earth to death, it just aged everything forty years. Later, the Doctor was able to erase this timeline by linking the Utopian Engine to the TARDIS and using it to turn time back to the day when the Eternians first made contact with Earth, erasing their influence. (PROSE: Reckless Engineering)