[ExI] Getting into space cheaply

[Keith Henson]

On Sun, Nov 27, 2011 at 5:00 AM,  Adrian Tymes <atymes at gmail.com> wrote:

> How do you get the energy to the rocket on the far side of the planet from
> the beam source?  Or would this require multiple beam emitters, spread
> around the planet?

It goes into orbit in less distance than what you can see from GEO, in
the particular run on that spread sheet it took about 4,600 km to
reach orbital speed.

Anders Sandberg <anders at aleph.se> wrote:

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

This is a teakettle design.  Surface skin is full of channels where
the hydrogen is pumped.  Overall reradiation loss is around 10% at
this temperature.

Keith