• Yomiuri Editorial

Lunar Surface Landing: Global Accomplishment Achieved, But Challenges Remain

More than half a century has passed since humankind embarked on lunar exploration, and interest in the moon is once again on the rise. Japan should use this latest accomplishment as a stepping stone to join in the international competition over development of the lunar surface.

The Japan Aerospace Exploration Agency’s (JAXA) lunar probe SLIM (Smart Lander for Investigating Moon) has landed on the lunar surface. This makes Japan the fifth country to have successfully landed on the moon, following the former Soviet Union, the United States, China and India. This can be said to be a new milestone for Japan’s space development program.

Although the moon is smaller than the Earth, its gravity makes a successful soft landing on the surface no easy task. Countries have repeatedly failed in the past and in Japan last year, too, a private spacecraft from the space startup ispace, inc. attempted to land on the moon, but could not.

The key feature of SLIM is that it is small in size and light in weight. It demonstrated to the world “pinpoint landing” technology, which allows a spacecraft to land on a targeted spot. The significance of this achievement is great.

Conventional spacecraft have aimed for a flat surface with few obstacles and landed within a few kilometers of target sites. SLIM, on the other hand, is believed to have landed within 100 meters or less of its target site near a crater.

From now on, lunar landing technology is expected to shift from “landing where it can land” to “landing where it wants to land.”

SLIM uses a unique landing technique because it is designed to land on a slope near a crater. Abandoning the common method of landing upright with its four legs open, SLIM instead is designed to land with its body sideways as if it were falling down. This technology is a global first, and the developers deserve credit for their conception.

However, the landing via the new method cannot be said to be a complete success, and there are aspects that cannot be unreservedly celebrated. SLIM is believed to be unable to generate electricity due to the lack of sunlight on its solar panels. There may be some trouble with the position of the lander.

It is unfortunate that the onboard observation equipment and other equipment cannot be fully used due to this problem, which is likely to hinder scientific research of rocks and other activities. The cause of the malfunction should be analyzed and a path to recovery should be explored, even if there is only a slight possibility.

Attention should also be paid to the activities of the spherical robot that is believed to have been released onto the lunar surface. A toy manufacturer participated in the development of this robot, and it transforms on the lunar surface and crawls on the sand. If it can take pictures of the lunar surface, it will certainly attract the interest of children.

In a future lunar exploration project led by the United States, a Japanese astronaut is scheduled to step on the surface of the moon in the latter half of the 2020s or later. Japan should act as a core participant in lunar surface development while also utilizing the power of the private sector.

(From The Yomiuri Shimbun, Jan. 21, 2024)