Traveling back in time involves TimeSpace, not just time.

A planet travels around its star at over 100,000 Kilometers per hour (Km/h). Add to that the speed of the star traveling at over 800,000 Km/h around the galaxy. And one more, the galaxy is traveling in space at over 2.1 million Km/h.

As you can see, after a few days or months, the distances become incredibly long. But not for Commander Zoey, she has access to the TimeDim, a frictionless TimeSpace dimension that allow her to go back in time to almost any TimeSpace location in the present and the past.

Yet, there is a catch, the longer Commander Zoey goes back in time, the more her health can be damaged.