How long will it take to reach the closest earth like planet Using the engines today how long will take humanity to reach earth like planets?
HD 219134b is apparently closest "super earth"; 21 light years away.
New Horizons, our speediest yet, is currently running at about 15 km/sec relative to the sun.
At 9.46e12 km/lightyear HD 219134b is 2e14 km away 
At 3.16e7 seconds per year, New Horizons will travel about 4.74e8 km/year.
2e14/4.74e8 = 422000 years.

HD 219134b isn't even a very good earth; gravity is too high.