Space travel – it is a dream we all aspire to. Who wouldn’t want to walk on the surface of another planet and see the double sunrise of a distant world? Okay, so maybe these distant worlds are still very much a fantasy lived out by Star Trek ‘enthusiasts’ but eventually they will become a reality, but not in our lifetimes, which is a huge shame.
The closest worlds that the human race could visit would be the Moon and the planet Mars. To get there with today’s technology takes around a week for the Moon (around a quarter of a million miles away) and a full year and half for Mars. Our conventional solid state rockets are simply not powerful enough to speed spacecraft on their way fast enough for human timescales due to the vast distances involved in space travel.
So how can this be changed, short of inventing a warp drive (the kind of thing that powers the USS Enterprise at such unbelievable speeds as Warp 9!)?
There are some interesting means of space travel that are being investigated and in some cases even tested in real spacecraft. The most promising of all is also one of the cheapest, in terms of renewable energy at least: Solar Wind power. Essentially the solar wind is the energy burnt off by the sun as it burns its store of Helium and Hydrogen gases.
The solar system is full of solar wind and we can witness its effects with the Northern Lights as it interacts with planet Earth’s atmosphere. If there were a way to harness this immense store of energy then it would be a totally free and renewable source of motive power. Here comes the downside; to capture even a part of this energy requires a spacecraft with a sail, like the old sailing ships tapping the power of the maritime winds but scaled up somewhat. I say somewhat, probably by a factor of around 100 to 250 times. The sail would have to measure around the size of 100 football pitches, but could be gossamer thin. To construct such a spacecraft would be an incredibly difficult task for any engineer made even more so by the fact that it would undoubtedly have to be built in space in zero G conditions. The benenfits though would outweigh these considerations with speeds expected to eventually exceed any existing spacecraft such as Voyager One and Two.
Another form of space propulsion being investigated at present is Ion Drive. Indeed these spacecraft are already in service in space and provide a steady stream of positively charged ions being forced out of the spacecraft in the same way a conventional rocket burns fuel. Ions, however, travel faster and as a result make the spacecraft travel faster as a consequence.
These are just two new forms of space propulsion that will have to suffice until someone invents a proper fully functioning Warp Drive or Hyper Drive propulsion system for spacecraft.