a large source, but on a smaller area of retina. However, with extended viewing times as are relevant to this problem, the eye's nystagmus or jitter is an important factor. It averages the retinal image over a large area-usually taken as 10-11 mrad, or at least 1/2 degree (15). So, the larger the retinal image of a point source, the larger the average retinal irradiance over the 1/2 degree (actually 180 pm dia.) area. We approximate this by weighting the irradiance Eg for the percent of the solar disc projected on the retina, (in this case 17 percent). To calculate the maximum safe exposure time (duration t max), we take the irradiance on earth from the whole solar disc at zenith in summer weighted For the next to the worst case, specular reflections from the flat aluminum back of the OTV panels in LEO, the same size retinal image pertains. A reflection factor of 0.33 must be introduced. So that: The next most dangerous condition would be a misallignment of the satellite to reflect an image of the sun on earth from GEO. In this case, the blue irradiance would be weighted by:
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