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The purpose of the LYRA mission is a multi-color all-sky survey of objects from 3 m to 16 m from the International Space Station, to result in a high-precision photometric catalog (Zakharov et al. 2013b). The expected error of the catalog will be 0.001−0.003 m for stars brighter than 12 m and 0.01 m for the stars down to 16 m . The estimated duration of the survey is about 5 years. This paper describes the characteristics of data to be received in the course of the LYRA experiment for future users. Equipment and principles of the surveyThe LYRA experiment will use a telescope with the mirror diameter of 0.5 m and the focal length of 3 m, built according to a quasi-Ritchey-Chretien scheme. In the focal plane of the telescope, a mosaic of 22 CCDs with 11 different filters is located. The telescope will make observations in a scanning mode, and the CCDs will detect images in the TDI (Time Delay and Integration) mode. To do this, the telescope is fixed with respect of the body of the International Space Station (ISS), and CCD mosaic columns are oriented along the direction of star-image motion.Scanning is performed by the orbital motion of the ISS, during which the ISS has an orientation with one axis of the station always facing the Earth and another axis directed along the orbit. As a result, the station makes one turn around the third axis in the time of one orbital revolution. The rotation of the station leads to changing orientation of the telescope, with a displacement of star images in the focal plane. The main orientation of the telescope's sighting axis lies in the plane of the orbit of the ISS. During one revolution, the sky is scanned along a great circle band with a width of 1• (actual observations are made only on the part of the loop where illumination from the Sun is small). The ISS orbital inclination is 51.6• . Because of the orbit precession, the nodes of the orbit move by 0.3• in one orbital revolution. This shift is smaller than the width of the scanning strip. The combination of orbital and precession motion permits to observe all objects with |δ| < 51.6• (see Fig. 1, left part).To observe the polar regions, the telescope axis should be inclined by 38.4• to the north or south, and the scan will go along a small circle of the celestial sphere that passes Corresponding author: zakh@sai.msu.ru through the celestial pole (see Fig. 1, right part). The combination of these three modes makes observations cover the entire celestial sphere.If the observations are performed during 50 % of all time, the annual average number of observations for a point of the celestial sphere is 22, and in 5 years, 110. Structure and functioning of the focal planeIn the focal plane of the LYRA telescope, 22 CCDs, 2250 × 300 pixels in size, are located. The pixel size is 12 μm (0.8 ). Images of stars move along the short side of the CCD. In the mosaic, pairs of CCDs with similar filter coating are collected by two in one case and joined by the short side (see Fig. 2). During scanning in small circles, these CCDs are given ...

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