Can Beamed Propulsion be a Viable Method to Reach Pluto?

[RobertGC]

The New Horizons results on Pluto are tantalizing. I was trying to come up with methods to get an orbiter or lander there. The problem is at a 31 AU distance from Earth solar power would only be 1/1000th as strong. However, with parabolic mirrors or Fresnel lenses we could focus a large amount of the light even very far away. A 10 square meter collecting area at Earth would collect 10,000 watts of solar energy. How much of this power could focus at 31 AU away?
This is beamed energy propulsion without using the laser. I wanted to avoid the laser so as to not have the problem of lofting the large mass needed for getting the high power laser to space.

Bob Clark

 

[Dr. Courtney]

https://www.nasa.gov/sites/default/files/files/CTaylor_SEP.pdf

https://en.wikipedia.org/wiki/Solar_thermal_rocket

 

[Drakkith]

A 10 square meter collecting area at Earth would collect 10,000 watts of solar energy. How much of this power could focus at 31 AU away?

Very, very little. You cannot focus light down to a spot 31 AU's away. It will simply diffract and spread outwards.