Japan's long-planned "Smart Lander for Lunar Exploration" (SLIM) has successfully landed on the lunar surface, becoming the fifth country in history to successfully land on the lunar surface. However, SLIM is not a be-all and end-all, and its lifespan may be limited due to problems with the solar cells.
At a press conference after the moon landing in the early morning (local time), JAXA and the mission's leader explained: "The soft landing itself was successful; SLIM has been communicating and receiving instructions. However, the solar cells do not currently appear to be generating electricity as planned."
Solar cells are prone to problems, as are other electrical devices in space, and the team hasn't been able to pinpoint the problem. However, since the other sensors were working fine and showing a healthy status, they were confident that the problem was limited to the solar cells themselves.
Using its own batteries is certainly not a long-term solution, and if they don't manage to get the batteries online, the main lander will only have a few hours of life (and could actually reach the end of its life at any time).
Landing on the moon is not an easy task. In fact, in the past few years, multiple countries and private companies have tried, but none of them succeeded. Something as small as a stuck valve (such as Astrobotic's recent mission) may cause the failure of the moon landing plan.
Based on telemetry data, there is some speculation that the lander may have tilted or be in some non-optimal physical condition, but so far JAXA has not confirmed this. The initial press conference was devoted to announcing the initial success of the soft landing and normal operations of the lunar lander.
However, the team did note that the two lunar exploration vehicles carried by SLIM appeared to have successfully deployed. The two sub-vehicles are ejected from the main aircraft while it hovers a few meters above the ground and will operate semi-independently from the main aircraft.
LEV-1 and LEV-2 (as they are called) should be able to capture images of the landing zone and SLIM itself, but "unfortunately, we can't show that to you right away," they said. If the sub-aircraft works properly, JAXA should release this information soon.
This matter is ongoing and we will update as new information becomes available from the Japan Aerospace Exploration Agency.