The Human Eye in Space :: essays research papers

Human ocular hardware is a case of a billion yearsof evolution within the earths atmosphere where absolved is scattered by molecules of air, moisture,particular matter etc. However as we ascend intoour atmosphere with decrease density, lightdistribution is changed resulting in our visualhardware receiving visual data in different format.Some Aspects to exact 1. optical acuteness is thedegree to which the details and contours ofobjects are perceived. Visual acuity is usuallydefined in terms of tokenish separable.Largevariety of factors solve this complexphenomenon which includes Optical factors-state of the image forming mechanisms of the eye. Retinal factors such as the state of the cones. Stimulus factors such as illumination, brightness ofthe stimulus, contrast surrounded by the stimulus andbackground, length of time exposed to thestimulus. * Minimum separable shortest blankby which two lines can be separated and still beperceived as two lines. "During the day, the e arthhas a predominantly dismal cast..... I could detectindividual houses and streets in the low humidityand unclouded areas such as the Himalayamountain area.... I saw a go locomotive byseeing the smoke first..... I also saw the wake of aboat on a large river in the Burma-India area...and a bright orange light from the British oilrefinery to the second of the city (Perth,Australia.)"The above observation was made by GordonCooper in Faith 7 1963 and which generatedmuch skepticism in the light of the dissertation byMuckler and Narvan "Visual Surveillance andReconnaissance from space vehicles" in whichthey situated that a visual angle of ten minuteswas the operational minimum, and that theminimum resolvable object length M.R.O.L at analtitude of 113 miles would be 1730 ft. This restriction of acuity was revised the next year to 0.5seconds of arc for an extended secern lineand 15 seconds of arc for minimum separation oftwo points crisply contrasting with thebackground . Orbiting at 237 miles in the skylab itwas possible to see the entire eastern coast Canadato Florida Keys and resolve details of a 500 feetlong duo based on inference. Of Interest is thefact that even though the automatonlike eye camerasystems can resolve objects greater than fiftytimes cave in than the human eye, without thehuman ability to infer, interpretation of the data ismeaningless. Conclusion Visual acuity in spaceexceeds that of earth norm when objects withlinear extension point such as roads, airfields, wake ofships etc. 2. Stereoscopic vision the percept oftwo images as one by means of fusing theimpressions on both(prenominal) retinas. In space one has todeal with a poverty of reference points.