Q&A: General Astronomy and Space Science
Is it possible to travel into the future by traveling the
speed of light around the Earth for an entire year inside a
spaceship that is going the speed of light?
No, but it might seem that way when you return to Earth. It
is impossible for objects with mass to travel at the speed of
light, but if you could devise a way to travel very close to
the speed of light, clocks in your space craft will run more
slowly than ones on Earth, so you would age more slowly. For
example, if you travel for a year at 99.98% of the speed of
light, you would find upon your return that everyone on Earth
had aged 50 years.