The difference that low earth orbit makes in an astronaut's life span may be negligible - better suited for jokes among siblings than actual life extension or visiting the distant future - but the dilation in time between people on Earth and GPS satellites flying through space does make a difference. This not-to-scale image shows the constellation of GPS satellites whizzing around the Earth in distant orbits. 'Now I've got that over his head.' General relativity and GPS time travel 'So, where I used to be just 6 minutes older, now I am 6 minutes and 5 milliseconds older,' Mark Kelly said in a panel discussion on July 12, 2020, previously reported. The difference in the speed at which they experienced time over the course of their lifetimes has actually widened the age gap between the two men. Scott Kelly spent 520 days in orbit, while Mark logged 54 days in space. Astronaut Scott Kelly was born after his twin brother, and fellow astronaut, Mark Kelly. While we don't accelerate humans to near-light-speed, we do send them swinging around the planet at 17,500 mph (28,160 km/h) aboard the International Space Station. An observer traveling at high velocity will experience time at a slower rate than an observer who isn't speeding through space. And third, nothing can go faster than the speed of light.įrom those simple tenets unfolds actual, real-life time travel. It stays the same no matter what, and no matter where it's measured from. First, all things are measured in relation to something else - that is to say, there is no 'absolute' frame of reference. The short version of the theory is deceptively simple. Special relativity describes the relationship between space and time for objects moving at constant speeds in a straight line. Along with his later expansion, the theory of general relativity, it has become one of the foundational tenets of modern physics. (Image credit: Getty) (opens in new tab)Įinstein developed his theory of special relativity in 1905.

Twin brothers Scott and Mark Kelly are both astronauts, and have both participated in landmark studies about the effects of space on the human body.

Dishonored 2 mission 7 dining room