The “Smart Lander for Investigating Moon” (SLIM) at the satellite fairing assembly building at the Tanegashima Space Center, Kagoshima prefecture. Photo: JAXA/ AFP.
Japan, on Saturday, became the fifth nation to achieve a soft lunar landing, but said its “Moon Sniper” spacecraft was running out of power due to a solar battery problem.
After a nail-biting 20-minute descent, space agency JAXA said its Smart Lander for Investigating Moon (SLIM) had touched down. And communication was established.
But without the solar cells functioning, JAXA official Hitoshi Kuninaka said the craft would only have power for “several hours”. The spacecraft is dubbed the “Moon Sniper” for its precision technology.
SLIM is one of several new lunar missions launched by governments and private firms, 50 years after the first human Moon landing.
Crash landings and communication failures are rife. But only four other countries have made it to the Moon: the United States, the Soviet Union, China and, most recently, India.
As mission control prioritised gathering data while they could, Kuninaka suggested that the batteries might work again once the angle of the sun changed.
“It’s possible that it is not facing in the originally planned direction,” he told an early-hours news conference.
“If the descent was not successful, it would have crashed at a very high speed. If that were the case, all functionality of the probe would be lost,” he said.
“But data is being sent to Earth.”
Prime Minister Fumio Kishida called the landing “very welcome news”. But he said he was aware that more “detailed analysis” on the solar cells was needed.
NASA chief Bill Nelson tweeted his “congratulations (to Japan) on being the historic fifth country to land successfully on the Moon”.
“We value our partnership in the cosmos and continued collaboration,” he added.
‘Big success’
JAXA hopes to analyse data acquired during the landing. This will help determine whether the craft achieved the aim of landing within 100 metres (yards) of its intended landing spot.
SLIM was aiming for a crater where the Moon’s mantle, the usually deep inner layer beneath its crust, is believed to be exposed on the surface.
Two probes detached successfully, JAXA said. One with a transmitter and another designed to trundle around the lunar surface beaming images to Earth.
This shape-shifting mini-rover, slightly bigger than a tennis ball, was co-developed by the firm behind the Transformer toys.
While the accuracy of the touchdown needs to be verified, Harvard–Smithsonian Center for Astrophysics astronomer Jonathan McDowell said: “I think the mission is a big success.”
Several things could have caused the solar panel problem, he told AFP.
“A wire came loose, a wire was connected the wrong way. Or the lander is upside down and can’t see the sun for some reason,” McDowell speculated.
The scientist added that “hopefully” JAXA had been able to download images from the landing. But, he said, an experiment to study the composition of Moon rocks may be a lost cause.
Renewed interest
Russia, China and other countries from South Korea to the United Arab Emirates are also trying their luck to reach the Moon as Japan has.
US firm Astrobotic’s Peregrine lunar lander began leaking fuel after takeoff this month, dooming its mission.
Then contact with the spaceship was lost over a remote area of the South Pacific on Thursday. It likely burned up in the Earth’s atmosphere on its return.
NASA has also postponed plans for crewed lunar missions under its Artemis programme.
Two previous Japanese lunar missions — one public and one private — have failed.
In 2022, the country unsuccessfully sent a lunar probe, named Omotenashi, as part of the United States’ Artemis 1 mission.
In April, Japanese startup ispace tried in vain to become the first private company to land on the Moon, losing communication with its craft after what it described as a “hard landing”.
