First potentially habitable Earth-sized planet

[Fusa]

Originally Posted by Gogan

Even it was 4 light years away (distance to the nearest star) it would still be too far.

as of right now that is correct, and I did read that, (not talking nuclear) sorta funny he doesn't even use a combination of all the things we have (right now for the theoretical fastest). If you used plantary/then short chemical/then ion thruster for the rest of the duration would far exceed any of the time frames giving for any of them (by them selves)

"Assuming all the 81.5 kg of xenon propellant translates into a maximum velocity of 56,000 km/hr (assuming there is no other forms of propulsion, such as a gravitational slingshot, and this velocity remains constant for the duration of the journey), Deep Space 1 would take over 81,000 years to travel the 4.3 light years (or 1.3 parsecs) from Earth to Proxima Centauri."

Once you can go even 75% of the speed of light it makes it more attainable ( in the span of ones life)

500 light years would ( never ) happen period.