[ExI] Getting into space cheaply

[Anders Sandberg]

Keith Henson wrote:
> It involves using beamed energy heated hydrogen that is combined with
> ram air as long as there is air to scoop up.  The average eqivalent
> exhaust velocity all the way to LEO is around 20 km/s, even better
> than Skylon at 10.5 km/s to when it runs out of air.
>   

Any more thoughts about what opaqueing agents to use to make the laser 
heat the hydrogen efficiently? Or does this design not require them?

-- 
Anders Sandberg,
Future of Humanity Institute
Philosophy Faculty of Oxford University