Time dilation occurs to any thing that moves and slows it down for the moving object.

However, even at the relatively high speeds at which the space station or other orbiting craft are travelling - 17,500 miles per hour (or 28,000 kilometers per hour for you Europeans) - the slowing of time that occurs is tiny. Even on record length trips into space that have lasted over a year astronauts have not even gained one single second.

The science fiction-like idea that a space traveller could leave Earth travel for a day, a week or a month and come back to find his friends and family were long-dead and he could meet his descendents, will remain fiction for the forseeable future.

To accelarate to the kind of speeds required for this to happen within these short time periods would put such huge g-forces on the traveller they would be squashed flat.

Human ingenuity is boundless and no-doubt one day we will work out how to achieve this - whether anybody would want to is another matter!