Japan successfully landed on the moon, but it may face some technical problems

On Saturday, Japan successfully landed on the moon with its Smart Lander for Investigating Moon (SLIM), making it the fifth country to nail a soft landing.

Japan successfully landed on the moon, but it may face some technical problems
People applaud after a moon landing by the Smart Lander for Investigating Moon (SLIM), in a public viewing event in Sagamihara, south of Tokyo, Japan January 20, 2024. REUTERS/Kim Kyung-Hoon

The backstory: The world has been in a space race lately to successfully land on and explore the moon. The US is expected to attempt around five moon landings this year through private companies, and last August, India became the fourth nation in the world to complete a successful soft lunar landing with its Chandrayaan-3. More than 10 years ago, China was the first to carry out a soft lunar landing in nearly 40 years. But landing on the moon has proved to be much more challenging than hoped. Russia’s Luna-25, the nation’s first moon mission in nearly 50 years, crashed on the lunar surface last year. Japan’s ispace also attempted a moon landing last year, but the lander suddenly accelerated and is thought to have crashed on the surface. So far, private companies have a 100% failure rate for landing on the moon.

More recently: Japan, wanting to make its own mark in space, has partnered with the US in its space program to counter China. Japan’s also home to several private-sector space startups. Its space agency, the Japan Aerospace Exploration Agency (JAXA), is aiming to send an astronaut to the moon in the next few years with help from US agency NASA. But, the nation’s faced multiple difficulties in its rocket development, with a failure to launch its H3 rocket (meant to match the cost-competitiveness of commercial companies like Elon Musk’s SpaceX) in March. This failure caused delays in the country’s space missions, including that of a joint lunar exploration with India. 

The development: On Saturday, Japan successfully landed on the moon with its Smart Lander for Investigating Moon (SLIM), making it the fifth country to nail a soft landing, after the Soviet Union, the US, China and India. Despite this success, though, the SLIM is having problems with its solar-powered system, meaning the craft will not be able to generate electricity. It had to rely on its batteries, which would only last for a few hours. While it’s not clear why the solar-powered system isn’t working, it’s possible that the solar cells became disoriented and aren’t facing the sun. But, as the light angles change on the moon, SLIM just might come back to life – fingers crossed. JAXA focused its efforts on retrieving data about how well the landing software worked and collecting pictures from the craft. It can take around 30 days for the sun's angles on the moon to switch up, so we’ll know more then about whether or not the craft might still have a chance to complete other parts of its mission.

Key comments:

"If powered descent wasn't successful, then there would have been a collision with the surface at a very high speed and spacecraft function would have been completely lost," JAXA Vice President Hitoshi Kuninaka told reporters. "But it is still sending data properly to us, which means our original objective of a soft landing was successful."

"It takes 30 days for the solar angle to change on the moon," Kuninaka said. "So when the solar direction changes, and the light shines from a different direction, the light could end up hitting the solar cell."

"We're in an era of a lot of lunar missions happening with lots of different players. If we collate all this knowledge, that all these players are gaining through these attempts - whether successful or not - then we learn as a community how to put missions together more successfully in the future," said Dr. Simeon Barber from the UK's Open University to the BBC.

"It's historic for them; it is a matter of prestige. It is important for Japan as a country; it's important for all the investment they have made - proof that it can be done by a country not as big as China or US," said Dr. Emma Gatti, from the digital magazine SpaceWatch Global, about Japan’s successful landing.