HELSINKI — Japan’s SLIM moon lander has entered a lower, near-circular lunar orbit ahead of its Jan. 19 landing attempt.

The Smart Lander for Investigating Moon (SLIM) initially entered lunar orbit Dec. 25, following an elongated, 110-day journey to the moon.

The spacecraft completed an orbit-lowering maneuver at 3:32 a.m. Eastern Jan. 14, the Japan Aerospace Exploration Agency (JAXA) announced. SLIM’s initial 600 x 4,000-kilometer polar lunar orbit has been lowered into a near circular 600-kilometer orbit. The spacecraft’s navigation camera captured images of the lunar surface during the maneuver.

JAXA also confirmed that preparations for landing and descent are complete. The landing will begin at 10:00 a.m. Eastern (1500 UTC) Jan. 19 (00:00 JST, Jan. 20), with touchdown around 20 minutes later.  

Live coverage of the landing attempt will begin around an hour before the start of the landing attempt.

SLIM will lower its perilune, or closest approach to the moon, to 15 kilometers Jan. 19 Japan time in preparation for the landing. The start of the landing process will see SLIM begin to decelerate from a speed of around 1,700 meters per second.

The spacecraft is targeting a landing within a 100 meters of a determined point on the slope of the mid-latitude Shioli crater.

Five crushable, 3D-printed aluminum lattice landing legs will help the lander absorb the impact of touch down and settle on the sloped rim of the 300-meters-wide Shioli crater.

Illustration showing how SLIM intends to land on the moon. Credit: JAXA

A successful SLIM landing would make Japan the fifth country to soft land on the moon. In August India became the fourth nation to achieve the feat with its high latitude Chandrayaan-3 mission landing.

After landing SLIM will spend the remainder of the lunar day in Shioli crater conducting experiments. SLIM carries a Multi-Band Camera (MBC) to assess the composition of Shioli crater by analyzing the spectra of sunlight reflected off its surface. Teams are particularly looking for the presence of olivine, a mineral which may have been ejected from beneath the moon’s crust.

SLIM is also carrying a pair of small, innovative rovers. Lunar Excursion Vehicle 1 (LEV-1) uses a hopping mechanism, while LEV-2 is a baseball-sized, spherical rover. Both carry cameras and science payloads.

Japan conducted its first launch of the year Jan. 12 (UTC), with a H-2A rocket carrying the IGS-Optical 8 reconnaissance satellite. JAXA and MHI are also preparing for the second launch of the new H3 rocket in mid-February.

SLIM itself launched Sept. 6, 2023, on a H-2A rocket from Japan’s Tanegashima Space Center along with the XRISM space telescope, for which NASA and JAXA are currently performing troubleshooting. SLIM initially entered a low Earth orbit and began a series of orbit-raising maneuvers as part of its circuitous voyage to the moon, arriving Dec. 25.

SLIM is one of a number of 2024 lunar landing attempts. U.S. firm Astrobotic’s Peregrine spacecraft, unable to land on the moon because of a propellant leak, is expected to reenter Earth’s atmosphere on Jan. 18.

China is meanwhile gearing up for an unprecedented lunar far side sample return mission around May, while Intuitive Machines is planning up to three landings. The first, IM-1, is scheduled to launch in February.

Andrew Jones covers China's space industry for SpaceNews. Andrew has previously lived in China and reported from major space conferences there. Based in Helsinki, Finland, he has written for National Geographic, New Scientist, Smithsonian Magazine, Sky...