Time dilation is a phenomenon predicted by the theory of special relativity. It occurs when there is a relative motion between two observers or when there is a difference in gravitational potential between them.
In the context of relative motion, time dilation arises from the fact that the speed of light is constant in all inertial reference frames. According to special relativity, as an object moves faster relative to another, time appears to pass more slowly for the moving object as observed from the stationary frame. This means that an observer in motion experiences time passing more slowly compared to an observer at rest.
To illustrate this, let's consider the twin paradox scenario. If one twin remains on Earth while the other travels at high speed to a distant star and back, the traveling twin experiences time passing more slowly relative to the twin on Earth. This is because the traveling twin's velocity relative to the stationary twin is significant, causing time dilation effects.
Regarding your question about the difference between time on Earth and time in space beyond Earth, it's important to note that time dilation is not solely dependent on the location but rather on the relative motion or gravitational potential. Time dilation can occur both in space beyond Earth and on Earth itself, depending on the circumstances.
In the case of gravitational time dilation, a difference in gravitational potential between two observers causes a difference in the passage of time. This effect can be observed, for example, near massive objects like black holes or even in weaker gravitational fields such as on Earth's surface.
In summary, time dilation is not purely determined by the difference between time on Earth and time in space beyond Earth. It is a consequence of relative motion or differences in gravitational potential, as described by the principles of special relativity.