Time dilation[3].
The spacecraft clock shows less elapsed time than the Earth clock.
For the depicted times, the spacecraft is moving at 0.80c.

A Starship Bathed in Heat, and not a Star Nearby

by Jeff Lee

Einstein’s Special Theory of Relativity tells us that the speed of light, c, is nature’s speed limit. All particles of pure energy are locked at this speed, and all matter particles always move more slowly than c. Thus, running a fair race[1] with a light beam is not only a fool’s errand, but it would constitute proof that a village somewhere is missing its idiot. However, physics doesn’t prevent us from getting arbitrarily close to the speed of light. 99% of c is perfectly okay, as is 99.9999% of c. There is simply no way to gain that “last 9” to bring us to light speed.

Although the speed of light is very fast (a whopping 300,000 kilometers per second), the stars are very far away. Thus, the exploration of distant star systems begets the obvious requirement for very fast subluminal (slower than light speed) starships.

“I Feel the Need…The Need for Speed”[2]

As a ship approaches the speed of light, the remarkable phenomenon of Time Dilation becomes prominent. The astronauts on board a relativistic starship would age less, maybe very much less, than the rest of humanity left behind on Earth. With sufficient speed, a vehicle manned by its intrepid crew could voyage across the Milky Way galaxy within a crew member’s lifetime. However, the speeds needed to complete such a journey within a human lifespan are indeed daunting.

Read more: A Starship Bathed in Heat, and not a Star Nearby | Icarus Interstellar.

Home           Top of page