The GFP Imaging System (GIS). (A) A photograph of the GIS hardware with the 6 slots for plates. Each slot is assigned a number (shown in red) to identify plate position: positions 1, 3, and 5 are on the bottom tier, and positions 2, 4, and 6 are in the top tier. The plate in position 1 is situated opposite the camera, which can collect both fluorescent- and white-light images of plate 1. (B) A side view of the GIS shows the configuration of plates 3 and 5. (C) On orbit, plates can be easily removed for harvest at the Maintenance Work Area (MWA), which is a surface in the US Lab of the ISS that is equipped for biological science, including a docking station for the GIS and a photogrid for the plates. The image shows an astronaut removing a plate from the GIS as well as a plate attached to the photo grid to the right of the GIS.