|Dr. Conca opines that investing in a backup planet might be a good idea, given what has been happening on Earth lately. The cost would only be a little over $20 trillion, but some nice real estate just came on the market. The discovery of seven Earth-like planets orbiting a nearby star has really gotten everyone thinking about space colonization again. Found by NASA orbiting Spitzer Space Telescope and the ground-based TRAPPIST Telescope, there seems to be at least seven Earth-sized planets orbiting the star TRAPPIST-1.|
The biggest surprise is that three or four of these planets are in the Goldilocks Zone, not too far from the star, not too close, not too big for a planet, not too small, a sweet spot where liquid water is stable on the right-sized planet with an atmosphere on which life could develop or survive if transplanted.
All these planets are similar to several planets in our own Solar System, but the fourth planet out, TRAPPIST-1e, seems the most favorable for life. Suddenly, we are talking about intelligent life elsewhere in the Galaxy, and travelling through space to get there. Is this desirable? Is it even possible? In this case, nearby means just under 40 light years away, a mere 230 trillion miles. Such a journey would take only a few years at 99.9999% of the speed of light or about 600,000 years at the fastest speeds we have recently attained with some clever slingshots around big planets.
So we just have to make a ship that can travel close to the speed of light. Over the years, many ideas have emerged to do that, mostly from nuclear fusion energy. But water must be present since it is the only compound with the necessary boiling and freezing points, thermal and electrical conductivities, density of its solid with respect to its liquid, is the most effective solvent, has great acid-base properties, etc.
But some researchers conclude that The Trappist system is not ideal ... http://bit.ly/2moxivT