Close to the Sun orbiting mirrors for beamed propulsion?

[RGClark]

NASA just announced a solar probe to travel quite close to the Sun, about 3.7 million miles from the solar surface:

Nasa’s hotly anticipated solar mission renamed to honour astrophysicist Eugene Parker.
Renamed the Parker Solar Probe to honour solar astrophysicist who predicted high speed solar wind, the spacecraft will attempt to get close to sun’s surface.
Wednesday 31 May 2017 07.08 EDT
https://www.theguardian.com/science...ticipated-mission-to-the-sun-solar-probe-plus

Spacecraft able to get this close to the Sun could potentially allow beamed interstellar propulsion. For a spacecraft of any size, you would need huge amounts of beamed power. Where to get it? If you make the beam be solar-powered then can just use space-borne mirrors to focus the Suns rays. But the mirror(s) would have to be impractically large if they were in Earth orbit.

But what if we placed them close to the Sun? At the distance quoted of 3.7 million miles away from the Sun a mirror 1 km on a side could collect a terawatt worth of power.

Bob Clark

 

[Donamy]

My prediction is ... it's very hot.

 

[MaverickSawyer]

I'd recommend reading John Ringo's "Troy Rising" series, just for the solar laser one of the characters created. Basically, he put a lot of mirrors into solar orbit, and used them to deliver absurd amounts​ of energy to... Well, wherever it was needed, whether to melt an asteroid, or to vaporize a hostile ship.

 

[Donamy]

Or make popcorn.

 

[Andy44]

I'd recommend reading John Ringo's "Troy Rising" series, just for the solar laser one of the characters created. Basically, he put a lot of mirrors into solar orbit, and used them to deliver absurd amounts​ of energy to... Well, wherever it was needed, whether to melt an asteroid, or to vaporize a hostile ship.

In Larry Niven's Ringworld Engineers, the Ringworld used magnetic lenses to channel stellar plasma into a gi-hugic laser which it used to defend itself from meteor strikes.

 

[Ravenous]

But what if we placed them close to the Sun? At the distance quoted of 3.7 million miles away from the Sun a mirror 1 km on a side could collect a terawatt worth of power.

Great idea, but my guess is it wouldn't have a very parallel beam. The sun's over a million km across (I think), a mirror 7-8 million km away would give a very widely spread beam.

(True lasers powered by solar panels might work though.)

 

[RisingFury]

Spacecraft able to get this close to the Sun could potentially allow beamed interstellar propulsion. For a spacecraft of any size, you would need huge amounts of beamed power. Where to get it? If you make the beam be solar-powered then can just use space-borne mirrors to focus the Suns rays. But the mirror(s) would have to be impractically large if they were in Earth orbit.

And when something gets hot, it expands, it bends, it warps. Have fun maintaining a good focus over hundreds of millions of kilometers.