This is concept art originally painted to help NASA and ESA imagine what it might be like to explore Jupiter and its moons Ganymede and Europa – part of push to explore “outer planets” and their moons.
The bottom ship is ESA’s JUICE – the Jupiter Icy Moon Explorer. You can read more about the originally proposed gas giant missions here, but as it stands, Europe is planning to launch this one without NASA’s help sometime in 2022.