The main role of Cupola is to serve as an observatory: it has a clear view of Earth and celestial bodies, and there enough space to accommodate two astronauts holding cameras with telephoto lenses.
Whether targeted Earth observations and scientific measurements or aesthetic and relaxing views, the scenery outside Cupola is impressive. From oil spills, desertification, melting icebergs and glaciers, dust storms, hurricanes and pollution to atmospheric phenomena and auroras – it is a lengthy list of targets.
Even now, when Earth can be studied all the time by many satellites with a variety of sensors, observations from the ISS are important, because there the observer is human. Astronauts not only adapt to changing situations, but also take photos spontaneously, when something interesting is happening.