Japan is preparing to land on the moon

Will Japan succeed in landing a drone on the moon? The SLIM probe is scheduled to land in the afternoon with greater precision than any lander before. Onboard instruments could also be useful for future lunar missions.

Japan could still come in fifth place in the race to the moon. A fourth place was within reach, but in April 2023, the specially developed Japanese Hakuto-R lander module malfunctioned and crashed on the moon's surface. India finished fourth a few months later.

So now Japan's next approach to the Moon and in fifth place – this time run by the state rather than the private sector. The SLIM Lunar Landing Module was built by the Japanese space agency JAXA and has been on its way to the Moon since September 7, more than four months.

Its somewhat complex approach, including orbiting the Earth several times, requires much less fuel than a direct launch, which would have taken SLIM to the Moon in just a few days. Since the Christmas holidays, SLIM has been in the Earth's satellite gravitational zone. The flight path was reduced several times. According to our time, landing is scheduled for 4:20 PM.

Landing Trick: The SLIM is designed to land in a targeted manner

The special feature of the mission: planning a precise landing. Until now, when landing on the Moon, it didn't matter whether the lander landed a kilometer or two away to the left or right. Reaching the moon's surface was never the priority. In the landing zone, which was often several kilometers wide, all points were equally interesting.

On the other hand, SLIM must fly to a specific landing point with an accuracy of 100 meters. The map of the Moon is now so precise that research teams want to look at smaller rock formations from a short distance, which requires the precise landing of a research module with cameras and measuring instruments in close proximity — no matter what surface it is on. Likes.

For example, the terrain in the SLIM landing zone rises an astonishing 15 percent toward the crater rim. The lunar lander therefore has a sophisticated landing procedure: instead of landing upright and risking accidentally tipping over, the device is deliberately tilted to the side upon landing. It is located on side-mounted landing legs, at the end of which a hemispherical shock-absorbing aluminum grille is mounted.

Rapid image evaluation for fine subsidence

SLIM can approach the landing site with such precision because it constantly takes images of the lunar surface and compares them with maps stored in the on-board computer. However, the rapid image evaluation required for this is not actually possible using computer chips that are currently best suited for space travel. Space devices hardened against cosmic radiation have only a hundredth of the computing power of those chips embedded in computers commercially available to terrestrial consumers.

But Japanese engineers were able to develop extremely fast software for the slow chips, which enabled rapid image evaluation needed for an accurate approach to the Moon.

A successful landing could pave the way to the moon base

If the precision landing is successful, it would also be interesting for another, more extensive lunar project. NASA wants to prepare for people to return to the Moon with unmanned cargo landers.

While the landing sites of the Apollo missions more than 50 years ago were in flatter, less obstructed terrain, Artemis 3 is scheduled to land at the moon's south pole in September 2026, an area filled with craters of all sizes. The sun permanently shines on some of the crater's raised edges, so that the lunar base could be supplied with solar energy around the clock – provided that cargo and people could be landed specifically in the obstacle-rich area.

In addition to accuracy when landing, the developers set themselves the goal of making SLIM particularly lightweight. For example, its solar cells are not rigid panels, but rather light, flexible films that can also be applied to curved surfaces. Every gram of probe weight saved saves fuel and allows for a greater payload of cargo.

Shipping moon reminds us Children's toys

On its maiden voyage, SLIM brought few instruments to the Moon, but it sure is entertaining. Shortly before landing, SLIM will take out two instruments on the lunar surface: a robotic lander, twice the size of a shoebox, which can hop on the lunar surface for 40 minutes after landing.

SLIM, on the other hand, carries a rover on board, which initially falls into the moon dust in the form of a ball only eight centimeters in diameter – a little larger than a tennis ball. Similar to a children's toy, it then changes shape using a folding mechanism in order to roll a few meters across the moon dust on two hemispherical wheels.

After two hours, its battery died. Anyone who suspects that a Japanese game designer is also part of the project team is absolutely right.

Analysis can Origin puzzle Solve

SLIM contains a spectroscopic camera for rock analysis. At the landing site, the 300-metre-wide Shiuli crater, olivine was discovered years ago by a Japanese satellite from lunar orbit. According to theory, this metal could only come from inside the moon. Studying it could help solve the mystery of how the moon was formed.