sc94597 said:
With a bussard ramjet and nuclear fusion reactors we can probably accelerate to something like 20% of the speed of light before the drag on the ship becomes too overwhelming. Solar sails are also predicted to have a maximum velocity of 10% the speed of light, so they are a (slower) alternative. We'd have to be careful of collisions though. At 20% of the speed of light a 1Kg object would have a kinetic energy of approximately 3.7 Petajoules. That is about ten times the energy yield of Little Boy. Although it wouldn't likely impart all of that energy on the ship. Fortunately interstellar space is mostly empty, and the ship likely could avoid any objects as big or bigger than that. It would take 400 years to get to the OP's system, a few years less from the perspective of the passengers. There is more about this method of space travel here. https://en.wikipedia.org/wiki/Space_travel_using_constant_acceleration I'd imagine we'd have technology that could achieve something like this a few hundred years from now (but maybe soooner or maybe later.) |
I linked this before which already has a theoretical upper limit of 26% the speed of light in just 10 minutes.
http://www.zmescience.com/space/lasers-mars-travel-04232/
The problem is how to slow down, and ofcourse it only works with very little mass.
Yet that does open the door to send out probes build in the form of a distributed redundant system made of thousands of smaller components under constant communication. A swarm of tiny objects is much more likely to survive mostly intact than a space ship. A distributed AI can control the swarm, make observations and beam results back to Earth.
Shielding a spaceship at those speeds is a big problem when a grain of dust is already enough to cause severe damage. Plus we dont know how dirty interstellar space is. The densisty of stray objects is likely a lot higher than in interplanetary space where the sun and planets have been cleaning up for billions of years. Distributed probes will be a lot more successful, although not as sexy as sending out the Enterprise.
Who knows if swarms of relativistic probes have already passed through our solar system, they would be impossible to detect. Yet even if they detected us and beam signs of our intelligent life back to their origin it could still be many millenia before the slow boat arrives. Physics is more cruel than nature. Bringing a life sustaining spaceship up to 20% of the speed of light for now seems suicide.