A Japanese company hoping to make history by carrying out the first private Moon landing says its mission is likely to have failed.
Communication was lost with the Hakuto-R lunar lander moments before it was due to touch down.
Engineers are investigating what happened.
The Tokyo-based iSpace had hoped the lander would release an exploratory rover, as well as a tennis-ball-sized robot developed by a toymaker.
The craft was launched by a SpaceX rocket in December, and has taken five months to reach its destination.
Those missions took only a few days to reach lunar orbit, but it took Hakuto-R five months. This was because it had a much less powerful propulsion system, in order to save fuel and reduce costs.
“We have not confirmed communication with the lander,” iSpace CEO Takeshi Hakamada said about 25 minutes after the planned landing.
“We have to assume that we could not complete the landing on the lunar surface,” he added.
The M1 lander appeared set to touch down around 1640 GMT on Tuesday after coming as close as 295 feet (89 m) from the lunar surface, a live animation showed.
The United States, Russia and China are the only countries to have managed to put a robot on the lunar surface, all through government-sponsored programmes.
