It'd take 200 years for the folks left on the planet but the folks travelling it would happen instantly, they'd not age a second during the time they were travelling at light speed.
really,,,,thats not what that brian cox fella said,,,rememberd his name...he said it would be the great great great grandchildren of the people that maned the space craft that would get to the nearest planet that might support life...
he also said it would take 6 years for the space craft to axcelerate up to light speed,,,and even then it would be just under light speed....
That's using the logic and scien