The world of space exploration and travel is, to say the least, as mind-boggling as it is seemingly infinite. While we know of neighboring stars and galaxies, actually getting to them with the current technology we have is nigh on impossible. In science-fiction movies, unsurprisingly, travelling from planet Earth to far flung places is generally no big deal. Yet, considering the nearest star system to our sun, Alpha Centauri, is a hefty 4.3 light years away, the idea of humans reaching just that any time soon is difficult to envisage.
For example, the space shuttles we have used to visit the moon travel at a maximum speed of about 28,300 KPH. At that rate it would take them about 165,000 years to reach Alpha Centauri. But there may be other ways to bridge such incredibly long distances. In fact, the film Interstellar could be seen as giving some insights into this.
One of these is called the Alcubierre warp drive, named after ideas put forward by Mexican physicist Miguel Alcubierre in 1994. He suggested that faster-than-light travel might be achieved by distorting space-time. A big obstacle with this is the energy required. In order to form the warp field/bubble, a region of space-time with negative energy density (i.e. going against space-time) is necessary. Scientific models predict exotic matter with a negative energy may exist, but it has never been observed.
If this concept worked, it would reduce the travel time to Alpha Centauri from thousands of years to just days. But with current technologies it's not possible. Another method is antimatter engines. This works on the principle that, when antimatter and matter meet, they annihilate each other, releasing vast amounts of energy. Scientists have observed bits of antimatter in certain locations. But no one knows how to create enough antimatter, or how to store it, for a trip to the stars.
However travel methods are just part of the problem. The real issue might be when to decide to go. Let’s say that faster-than-light travel isn't going to become a reality any time soon. Suppose we have to choose another mode of travel – a conventionally powered space craft of some kind or even an antimatter drive. Now suppose we leave for a trip among the stars. Suppose that, generations from now, our descendants arrive at a planet in the Alpha Centauri system. They might be greeted by fellow humans who left later but travelled via a more efficient process and so made the trip in a shorter time. It's not the destination, though; it's the journey getting there, right?
Prepared by: JZEnglish