Complex sentence: Despite its proximity, Barnard's Star, at a dim apparent magnitude of about nine, is not visible with the unaided eye; however, it is much brighter in infrared light than it is in visible light.
Split into simpler sentences: Despite its proximity, Barnard's Star at a dim apparent magnitude of about nine is not visible with the unaided eye. However, it is much brighter in the infrared light than it is in visible light.