Yousuf Khan wrote:

Small Engine For the Big Job of Testing Theory of Relativity | Universe
Today
"Twelve thrusters will be used for the LISA Pathfinder. Working together
with another propulsions system designed by NASA, the thrusters should
yield directional control at least 100 times more accurate than any
spacecraft before; down to a millionth of a millimeter. "
http://www.universetoday.com/2009/04...of-relativity/

Let's see now...

[10^(-6)][10^(-3) m] = 10^(-9) m or a nanometer.

How much thrust is imparted by the changing angle with orbit of solar
photons bouncing off, absorbed by, and absorbed and re-radiated by the
spacecraft?

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/lajos.htm#a2