Refraction Challenge

I read this as the station is visually acquired at the angle you specified. Why wouldn't you aim the laser at the visual target? Wouldn't the laser refract in the same way (direction) that the light reflection from the space station would?

Different wavelengths have slightly different refraction. I am not sure, but I seem to remember that an infrared (assuming for no reason whatsoever that the laser is infrared) has a slightly longer focal length than visible light so it refracts slightly less. If so, then I believe you would need to aim it slightly lower than line of visual sight.

Yes, 'Hero' had the correct answer: point the laser at the visual target. The arguments about different frequencies refracting differently can never account for half a degree 'upwards' or 'downwards' - those were the only other options in the question!

Red refracts more. An IR laser would have to be aimed slightly higher since it will be refracted more than the 1/2 degree for visible light. An UV beam would have to be aimed slightly lower as it will refract less so the beam would be aimed slightly more directly at the actual location (not the visual location).

Higher freq refracts more, but it is Snell's law that determines what position to aim at. We know the index of refraction will be less in space, If "downward" means closer to the normal (implying a greater index of refraction), then the exiting angle of Theta2 is smaller than the incident angle of Theta1. If "downward" means further away from the normal (implying a less index of refraction), then exiting angle of Theta2 is greater than that of incident angle, Theta 1. See Snell's law [n1*sin(Theta1)=n2*sin(Theta2)]. So the reference of the source must also be taken into account w.r.t to communicating the needed info. See http://66.102.7.104/search?q=cache:9FA0wV5ZGHIJ:sc ienceworld.wolfram.com/physics/SnellsLaw.html+what +is+snell%27s+law&hl=en&gl=us&ct=clnk&cd=1

Do you reckon there will be any significant difference in refraction between the visible spectrum light from the ISS and the laser beam towards it? (Granted, one should specify the laser frequency).

Says yoda. If the frequency is low enough it might skip back towards earth and not enter space at all. I think someone said do not shoot until you see the white of their eyes. But I may be out of context. I would wait until it I was sure I can send frequencies through atmosphere, then I would aim it at the target if I was using 'light' waves.

i'm in the air force national guard, and we use equipment that "bounces" waves off of the troposphere down to another location. this equipment is old now, its been around since the 1980's and is being phased out because of its age and as a result of being terribly inefficient.(only 3%-5%_of the transmitted signal is actually bounced back towards earth)