## WATCH | What happens to time when you travel at the speed of light?

### NASA has released a fun video that explains how you would age if you travelled through space at the speed of light.

• If you travelled at the speed of light, how would you experience time?
• Travelling in space for three years at close to the speed of light would equal five years on Earth.
• This indicates how an astronaut might age on a long space journey.

Want to leave the planet? It's safe to say that millions would like to do just that at this point in time.

But there are a few technical details that need to be figured out before space travel becomes more mainstream – including cracking the code of near-light speed travel.

NASA recently released a fun video, explaining some of the mechanics of travelling at this velocity, which is 90% of the speed of light. (Light travels at more than a billion kilometres per hour.)

Perception of time

One of the biggest adjustments would be your perception of time. While it might take you three years to reach the planet of your choice, on Earth, time would have moved a bit faster. To get to the edge of our solar system would take nine months, while on Earth, a year-and-a-half would pass.

Beyond our solar system, the next closest star system is Proxima Centauri, and it would take more than two years to get there at 90% of the speed of light.

Time dilation

This time differentiation is called time dilation. This is a fact of space travel that forms part of Albert Einstein's theory of relativity.

According to MIT Technology Review, if you left your twin behind on Earth, they would age more quickly than you.

However, the age difference would depend on the speed of the spaceship, including when it accelerates and when it slows down. Time dilation is also dependent on gravity and how close the "clock" is to a gravitational force like that of a planet.

Fast particles

Space also isn't exactly empty. You would, for example, need some sort of shield from free-running particles that could damage you and your spacecraft, as they can also travel at around the speed of light.

NASA explains that there are three ways that this acceleration can happen: through electromagnetic fields, magnetic explosions and wave-particle interactions. These mostly involve the collision of energies and magnetic fields.

Unfortunately, humanity is still a long way from having the kind of technology that allows us to reach these speeds.

For now, you can but daydream with NASA, while watching the video below:

Image credit: Pixabay

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