‘Mysterious’ surfboard-like object orbiting Moon is South Korean spacecraft

The "Moon surfboard" pictured by NASA's LRO was a South Korean spacecraft.

During the next encounter, LRO was closer to Danuri, about 2.5 miles, or 4 kilometers, and oriented 25 degrees toward it. NASA/Goddard/Arizona State University

NASA’s Lunar Reconnaissance Orbiter clicked a picture of what looked like a “surfboard” orbiting the Moon last month. The space agency said the picture was of Korea Aerospace Research Institute’s Danuri lunar orbiter as the two probes zoomed past each other.

LRO’s narrow-angle camera, one in a suite of cameras known as LROC, took this image during one of the three orbits during which it happened to be close enough to Danuri. The relative velocity between these spacecraft was about 11,500 kilometres per hour. This required NASA’s teams to have perfect timing to point LROC in the right direction and take a picture of the Danuri, which is South Korea’s first spacecraft on the Moon.

There is a reason for why Danuri has the long slender appearance of a surfboard. LRO’s camera exposure is very short at only about 0.338 milliseconds. But with such a high relative velocity, Danuri appeared 10 times its size opposite to the direction of travel.

Danuri is officially called the Korea Pathfinder Lunar Orbiter and it is developed and managed by the Korea Aerospace Research Institute (KARI) and launched in August 20222 to orbit the Moon for a year with both South Korean experiments and one US-built instrument. Its main mission objectives include proving lunar exploration capabilities, demonstrating “space internet,” and conducting scientific research and even identify future landing sites for missions.