Time sphere

The time sphere is a green, shimmering sphere that allows a user to travel into the past. However, it is a one-way trip&mdash;the sphere cannot be used to return to the future&mdash;and can only be summoned if the binary time code is spoken out loud. The time sphere is apparently under the stewardship of the Galactic Entity (and may in fact be the reason for its existence). When a summoner jumps inside, time goes slower, while they tell where to go.

Trivia

 * The only known people to have ever used the time sphere are Nudar, Bender, Chris Travers and Fry. Since it is a "one-way" trip (meaning that one can go backwards but not forwards in time), these four characters have different ways to combat this. Fry freezes himself in a cryogenic tube, Bender waits for thousands of years under the Planet Express building, Nudar simply lives for 24 hours (he only goes backwards by one day), and Travers just stayed where he was, as was planned so he could become President of Earth in 3012.
 * It should also be noted that all four interacted with their time travel duplicate; Nudar went out with his, Bender instructed his to wait for Fry, Fry argued with his, and Chris Travers helped with his own birth.