Experimental astronomical observation using a lobster eye optics

A lobster eye (LE) is a wide-field type of X-ray optics, which provides a large field of view at the expense of angular resolution. The optics presented in this paper are the LE optics in Schmidt arrangement made from glass sheets with golden reflective coatings. It was used as a scientific payload on the WRXR rocket experiment. Before the mission itself, the optics was tested on ground to obtain more information about its behavior. Part of these tests were several nights of observation at the Ondrejov observatory. We used the optics in combination with a CMOS camera to acquire images in visible light of various bright sources in the sky. In order to enable long-time exposures, the robotic mount of the BART telescope was used. The goal of this experiment was to confirm the focal length of the optics using a source at infinity, and to show how the optics, designed for X-ray observations, performs in visible light. This brief article describes the methods used for evaluation and presents and discusses the results obtained within the night observation experiment.