TIme+Dilation+JACOB


 * Time dilation** is a phenomenon described by the theory of relativity. It can be illustrated by supposing that two observers are in motion relative to each other, and differently situated with regard to nearby gravitational masses. They each carry a clock of identically similar construction and function. Then, the point of view of each observer will generally be that the //other// observer's clock is in error.

At the velocities people currently travel the effect of time dilation is small, but measurable with accurate instruments. Since time dilation affects the rate at which time passes, the total discrepancy between stationary and moving clocks increases throughout the voyage. You don't even have to go into orbit to measure time dilation. Modern-day atomic clocks are so accurate that when synchronizing clocks between different observatories, the effect of time dilation due to transporting the reference clock on an airline flight must be taken into account.