After eight failed attempts, it finally hit the bullseye.

Bullseye

NASA’s Lunar Reconnaissance Orbiter has been shooting lasers at Japan’s Smart Lander for Investigating Moon (SLIM) in an attempt to hit a retroreflector mounted right beneath the lander’s solar panels. This tiny, dome-shaped device called a Laser Retroreflector Array is a surprisingly simple contraption with an important job. It’s designed to reflect light, revealing its location to the original laser source with an extremely high degree of accuracy.

NASA is hoping the device could guide the way for future Artemis astronauts in the dark or help locate existing spacecraft on the lunar surface. Best of all, the device works without power, which means it could last for decades, according to the space agency.

After eight failed attempts, LRO’s laser finally hit the bullseye on May 24, bouncing light off of Japan’s SLIM — despite the lander failing to stick the landing and toppling over back in January.

“This was an important accomplishment for NASA because the device is not in an optimal position,” NASA wrote in a press release last week (in fact, SLIM landed “with its top facing sideways, limiting LRO’s range.”)

Moon Ping

Even if SLIM had landed perfectly, it was already a tough shot. The orbiter’s laser altimeter was originally designed to map the Moon’s topography, not shoot a tiny reflector on the surface.

“LRO’s altimeter wasn’t built for this type of application, so the chances of pinpointing a tiny retroreflector on the Moon’s surface are already low,” said NASA scientist Xiaoli Sun, who led the team that built the retroreflector attached to SLIM, in a statement.

“For the LRO team to have reached a retroreflector that faces sideways, instead of the sky, shows that these little devices are incredibly resilient,” he added.

The news comes after LRO successfully bounced a laser off India’s Vikram lander in December. Since then, the orbiter has hit the lander’s target three more times, according to NASA.

More on the tests: NASA Probe Shoots Indian Moon Lander With Laser