Japan's SLIM 'moon sniper' lander enters lunar orbiton December 25, marking a significant milestone in its quest for the nation's inaugural moon landing. The robotic SLIM moon lander successfully entered lunar orbit, according to an announcement from the Japan Aerospace Exploration Agency. The spacecraft accomplished this feat as scheduled at 2:51 a.m. EDT (4:51 p.m. Japan Standard Time, 07:51 GMT).
"The Japan Aerospace Exploration Agency (JAXA) is pleased to announce that the Smart Lander for Investigating Moon (SLIM) was successfully inserted into lunar orbit at 16:51 (Japan Standard Time, JST) on December 25, 2023," JAXA officials wrote in an update. The spacecraft is now in an elliptical orbit, completing a lunar circuit in 6.4 hours. It approaches as close as 373 miles (600 kilometers) to the lunar surface at its nearest point and extends outward to 2,485 miles (4,000 km) at its farthest.
This achievement keeps SLIM on track for its ambitious lunar touchdown scheduled for January 19, marking a potentially historic event. To date, only four nations - the Soviet Union, the U.S., China, and India - have successfully executed a soft landing on the moon.
An illustration of the SLIM moon lander floating close to the moon
Launched on September 6, the 8.8-foot-long (2.7 meters) SLIM embarked on its journey alongside XRISM, a powerful X-ray space telescope. Both spacecraft initially entered Earth orbit, with XRISM remaining in that position to this day. However, SLIM departed Earth's gravity well on September 30, following a lengthy, circuitous, and energy-efficient trajectory toward the moon.
Today, SLIM successfully inserted itself into lunar orbit, marking the end of its extensive journey. The probe will now prepare for its upcoming touchdown attempt, aiming to live up to its "Moon Sniper" nickname. SLIM aims to achieve a remarkable landing-zone accuracy of 330 feet (100 m) or less. This precision sets the stage for more ambitious exploration endeavors in the future.
SLIM "is a mission for researching the pinpoint landing technology necessary for future lunar probes and verifying this on the moon's surface with a small-scale probe," JAXA officials wrote in a mission description.
By creating the SLIM lander, humans will make a qualitative shift towards being able to land where we want and not just where it is easy to land, as had been the case before. By achieving this, it will become possible to land on planets even more resource-scarce than the moon.- JAXA officials
If the mission unfolds as intended, SLIM is set to deploy two mini probes onto the lunar surface following its touchdown. This subsidiary craft will be tasked with capturing photos, assisting mission team members in monitoring SLIM's status, and serving as an independent communication system for direct communication with Earth, as detailed in the SLIM mission's press kit by JAXA officials.
The Hiten probe and SELENE ("Selenological and Engineering Explorer"), also known as Kaguya, were the first Japanese spacecraft to enter lunar orbit before SLIM did so in 2007.
Additionally, Hakuto-R, a lander developed by the Tokyo-based company ispace, achieved lunar orbit in March of the current year. A month later, Hakuto-R attempted to land on the moon, but sadly, it crashed because the rim of a lunar crater confused its sensors.