Japan's SLIM moon lander regains power nine days after botched landing

Japan’s moon lander is back in contact with Earth, nine days after it entered a power-saving hibernation mode when it landed incorrectly and lost the ability to generate energy.

The Smart Lander for Investigating Moon (SLIM) touched down on 19 January, making Japan only the fifth country to have successfully landed a lunar spacecraft. SLIM managed to end up within 55 metres of its target location, using a new and precise landing system, but one of its thrusters failed during its descent.

The Japan Aerospace Exploration Agency (JAXA) quickly received information that the craft had landed upside down, with the solar panels facing the wrong direction to generate electricity.

For just over 2 hours, SLIM managed to collect and send back data and images to Earth using its backup power. However, that battery was only designed to work for a few hours, so JAXA engineers put the spacecraft into hibernation when it reached 12 per cent charge, in the hope that the solar panels might start working again at some point when the sun moved across the sky.

JAXA has now managed to reconnect with SLIM, receiving communications from the spacecraft on 28 January. The sun is now shining from the west in the lunar afternoon, onto SLIM’s solar panels. This has enabled the lander to continue its scientific operations, and it has already begun to analyse the rock composition near its landing spot.

Even with the extra power, the spacecraft has limited time to carry out its measurements. The lunar night will begin on Thursday and last 14 days. JAXA has previously said the lander isn’t designed to survive the dark, freezing conditions this will bring.

However, two small autonomous rovers that made the journey with SLIM were released upon arrival on the surface, and have already sent back pictures. These vehicles will keep exploring and sending back information even if the lander itself fails.