In the search for other habitable planets like Earth, there is a growing consensus that the Universe is so incredibly large that our planet can’t be the only one capable of harboring life. There must be others like this one, sitting a comfortable distance from its star, just the right size with just the right composition. It might have life on it, it might not, because the Universe is not only vast, it is ancient. Once upon a time this planet existed without life and the way we are going it will surely happen again.
The follow up question to this worthy endeavor is: Once we find it, how do we get there?
Presently, the answer is: we don’t.
Our closest neighbor, Alpha Centauri, is 4.3 light-years away. That translates to 25 trillion miles. With current propulsion technology it would take tens of thousands of years to reach that system. I’m not sure we have that kind of time. Scientist, engineers, governments and for-profit companies have a few ideas to get us that extra light year. Some are in the works and will help us in our home solar system. While others are hypothetical and still others theoretical.
Within the realm of modern possibility we have the Direct Fusion Drive (DFD). Nuclear fusion hasn’t been a successful or economical way to create thrust. It requires high heat and pressure to force the atoms to fuse and convert mass to energy. The researchers at the Princeton Plasma Physics Laboratory (PPPL) are modifying the concept to use radio-waves to heat a mixture of deuterium and helium-3 into a plasma ring that spirals out of the engine, creating thrust.
Getting to Mars using current technology takes two years. With the DFD it could take about 300 days. Saturn goes from a six year journey to two years and Pluto, once nine years away would be five. Cutting the journey time down has many advantages. Transports could carry less food and supplies and astronauts would be exposed to less radiation. They have yet to achieve fusion, but hope it will happen in the mid-2020s. After that, they are aiming for a demonstration flight around 2028.
As a Star Trek nerd, I’m jazzed on the concept of a real-life warp drive. It’s highly speculative, but theoretically possible. Originally proposed by Miguel Alcubierre, others have grabbed hold of the idea. Dr. Harold White wrote a paper on the plausibility of distorting space-time for space travel. It’s all over my head, but artist Mark Rademaker created some incredible images depicting what such a ship might look like. It’s certainly not possible with current technology and requires matter with negative energy, which might exist but we haven’t found it yet. If we ever do, it would make the trip to Alpha Centauri in a matter of days.
Speaking of habitable plants, check out our Out of this World article on two newly discovered planets!