The Rolis Experiment on Philae

Abstract

ROLIS (Rosetta Lander Imaging System) is one of the two imaging systems carried by the Rosetta’s Lander Philae. Consisting of a miniaturized CCD camera, ROLIS will operate as a descent imager, acquiring imagery of the landing site on comet 67P/Churyumov-Gerasimenko with increasing spatial resolution. After touchdown ROLIS will focus at an object distance of 30 cm, taking pictures of the comet’s surface below the Lander. Multispectral imaging is achieved through an illumination device consisting of four arrays of monochromatic light emitting diodes working in the 470-, 530-, 640-, and 870-nm spectral bands. The drill sample sites, as well as the Alpha X-Ray Spectrometer (APXS) target locations, will be imaged to provide context for the measurements performed by the in situ analyzers. After the drilling operation, the borehole will be inspected to study its morphology and to search for signs of stratification. Taking advantage of the Lander’s rotation capability, stereo image pairs will be acquired, which will facilitate the mapping and identification of surface structures.