The MASCOT lander carried on Hayabusa2 just landed on Ryugu, completed it's mission and finshed operation as it has a non-rechargeable battery and no means to generate power. See this answer for more on the lander's power allocation.
Before MASCOT two smaller landers (Rover-1A and Rover-1B) were deployed and they are still operating as they have solar panels.
My question is, why the designers of MASCOT left out solar panels?
Notes/thoughts: Asteroid Ryugu orbits the Sun in a distance of 0.96–1.41 AU, Rover-1A and 1B have only cameras and thermometers while MASCOT has a lot of scientific instruments (which might need a lot of power?), many of them located on the face of it, so the usable surface area looks small. Would it be too little and/or facing the wrong direction to be usable for solar panels?