A proof of concept for a frost detection imager using reflected starlight is presented; the limitations of this technique are explored experimentally. An ice-covered lunar surface is simulated inside a vacuum chamber, which is then illuminated with a lamp containing UV and visible output to simulate the wavelengths of the background starfield. The simulated lunar surface is imaged with a camera utilizing a UV and visible filter pairing. At Lyman-alpha wavelengths, ice has low reflectivity, and on average appears darker than the regolith in the UV image. In visible wavelengths, this behaviour is reversed, with ice appearing brighter than regolith. UV/VIS image ratioing is subsequently performed in order to discern frost from the lunar regolith simulant in order to demonstrate the capability of this technology for locating the presence of ice on the lunar surface. When the two images are ratioed, the signal to noise ratio to distinguish ice from regolith improves by 36%. In cases where the presence of shadows and specular reflection make distinguishing ice from regolith in either a single UV or visible image difficult, ratioing the images makes the distinction clear.

中文翻译：

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利用反射星光对永久阴影区月球冰成像的实验室研究

提出了使用反射星光的霜检测成像器的概念验证；这种技术的局限性是通过实验来探索的。在真空室内模拟冰雪覆盖的月球表面，然后用含有紫外线和可见光输出的灯照亮，以模拟背景星场的波长。模拟的月球表面是用一台利用紫外线和可见光过滤器配对的相机成像的。在 Lyman-alpha 波长处，冰的反射率较低，并且在紫外线图像中平均看起来比风化层更暗。在可见波长中，这种行为是相反的，冰看起来比风化层更亮。随后执行 UV/VIS 图像比率以从月球风化层模拟物中辨别霜冻，以证明该技术定位月球表面冰存在的能力。当将两幅图像进行比对时，区分冰和风化层的信噪比提高了 36%。如果阴影和镜面反射的存在使得在单个 UV 或可见光图像中区分冰和风化层变得困难，则对图像进行比例划分可以使区分清晰。