Originally Posted by David Jonsson

Hi

Can anyone help me determine how much data that is physically possible
to transport with a beam of light from Earth reflected on a satellite
back to Earth again with an good reflector?

I made a fast calculation on the moon and found that since the mirror
is distributed over a distance of 0.1 m a difference in time of the
signal of one nanosecond will occur limiting the bitrate to maximum
one gigabit per second which is not worth transporting. On the other
hand maybe 1000 different light frequencies can be used making it
possible to sell the data flow for $ 500 000 per month.

To find out if it is worth doing assume a transport price of 0.5 $ per
megabit per second for one month (approx 600 gigabyte per $).

Is it worth building, place in orbit and maintain such a satellite?

I can imagine a low orbit satellite with a big concave mirror, a plane
mirror in the focal point and another big concave mirror aiming the
reflected beam back to earth in a non diverging beam to another place
on Earth. Precision would be at least 1 000 higher than the Moon
example giving a cash flow of ½ billion $ per month.

How much would the atmosphere distort this signal?

Someone might complain about clouds blocking the signal but it would
anyway be valuable for cloud free moments. Internet operators could
save money whenever the sky is clear.

David

David Jonsson, Sweden, phone callto:+46703000370