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Japan's SLIM lunar probe returns to life more than a week after landing upside down

The solar panels recharged the probe's battery after the sun's orientation shifted.


Japan's lunar lander has regained power a full nine days after it landed on the moon's surface nearly upside down and was subsequently switched off, JAXA (Japan Aerospace Exploration Agency) announced. A change in the sun's position allowed the solar panels to receive light and charge the probe's battery, allowing JAXA to re-establish communication.

Things were looking dire shortly after the SLIM (Smart Lander for Investigating Moon) touched down. The agency immediately noticed a problem with power generation, but was able to launch a pair of probes onto the moon's surface. The Lunar Excursion Vehicle 2 (LEV-2) snapped an incredible photo of SLIM, showing it to be upside down with its panels pointing away from the sun. The cause was found to be a malfunction of the main engine.

JAXA thought there was a chance the probe could recover once the sun's rays pointed more toward the solar panels, and that's exactly what transpired. Shortly after power was regained, it snapped another picture of a previously imaged rock formation called "toy poodle" using a multi-band spectral camera. The team is also targeting several other rocks with canine-themed names, including "St. Bernard," "Bulldog" and "Shibainu."

The upside-down landing may have seemed like an unrecoverable fault, but it looks like the mission can now proceed more or less as planned. While the baseball-sized LEV-2 explores the surface (relaying data via the LEV-1 probe, which also has two cameras), SLIM will grab whatever science it can.

In any case, the mission was already deemed a success, as the primary goal was a precision landing. It did just that, hitting a spot just 55 meters (180 feet) of its target. It's not known how much longer SLIM can function, as it was never designed to survive a solar night and the next one happens on Thursday.