As we take our virgin steps into space, there is one thing that could always put a cap on our ambitions.
Despite our desire to explore the stars, we are limited by travelling at less than light speed - and even if we managed to match that pace, we would still be listing our voyages from star to star in years, centuries or millenia.
But, in what could be a huge breakthrough, theorists from Nasa say there is 'hope' that we can achieve faster-than-light travel, after physicists found a theoretical possibility for warp speed travel.

Space time mapped out: Teams at NASA are exploring ways to warp the universe to enable faster than light travel. Pictured is a model of how a ship, enclosed in a space-time 'doughnut', could reach the stars
While nothing can break the speed of light, scientists have long considered the fantasy of warp speed travel, where spaceships could bend space and time on itself to move through loopholes in space.
Equations based on the laws of relativity have allowed warp speed in theory: but the energy required to make it happen would require the energy-mass of a Jupiter-sized planet.