ROLIS (Rosetta Lander Imaging System) is an imaging system consisting of a miniaturised CCD camera. Its primary purpose was to operate as an imaging device during the decent of Philae, obtaining increasingly high resolution images of the landing site.
Once on the surface, ROLIS was supposed to take pictures of the surface below the lander. A series of light emitting diodes would have allowed this to be done using several wavelengths. In addition it would have provided support to the drilling instruments and to APXS, by imaging the resultant boreholes and by imaging the target locations respectively.
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