>”One Sun is NOT Enough”https://web.archive.org/web/20171129162846/https://alienpolicy.com/nasa-patent-artificial-sun/> …to provide a novel illumination system particularly suitable for use as a sun simulator in conjunction with an environmental test chamber; to provide a novel illumination system of this type in which the real light sources may be positioned exteriorly of the test chamber and their light outputs directed into a test chamber through a relatively small window; to provide an illumination system of this type which is of relatively simple and rugged construction and reliable and convenient in operation.”> In a sun simulator system, it is desirable to provide means for varying the intensity of illumination over a relatively wide range without change in the spectral distribution of the illumination, so that the simulator may be used to simulate not only sunlight, but also earthlight and moonlight.”> …to provide a novel illumination system particularly suitable for use as a sun simulator in conjunction with an environmental test chamber; to provide a novel illumination system of this type in which the real light sources may be positioned exteriorly of the test chamber and their light outputs directed into a test chamber through a relatively small window; to provide an illumination system of this type which is of relatively simple and rugged construction and reliable and convenient in operation.”More evidence :
https://m.youtube.com/watch?v=XjkIlARf31E(Check this guy’s entire channel good documentation).
Segmented mirrors for sun simulators:
https://www.amos.be/project/test-mise-en-pageBooks:
https://www.amazon.com/s?k=claudia+albers&i=stripbooks&ref=nb_sb_noss_1Germany’s artificial sun:
https://www.abc.net.au/news/2017-03-24/germany-fires-up-worlds-largest-artificial-sun/8382510 