After a nail-biting 20-minute descent, space agency JAXA said its Smart Lander for Investigating Moon (SLIM) had touched down and communication had been established.

But without the solar cells functioning, JAXA official Hitoshi Kuninaka said the craft -- dubbed the "Moon Sniper" for its precision technology -- would only have power for "several hours".

As mission control prioritised acquiring data while they could, Kuninaka suggested that once the angle of the sun changed, the batteries might work again.

"It is unlikely that the solar battery has failed. It's possible that it is not facing in the originally planned direction," he told a 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."

SLIM is one of several new lunar missions that have been launched by countries and private firms, 50 years after the first human Moon landing.

Crash landings, communication failures and other technical problems are rife, and only four other nations have made it to the Moon: the United States, the Soviet Union, China and most recently India.

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, which 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, "I think the mission is a big success," said Jonathan McDowell, astronomer at the Harvard-Smithsonian Center for Astrophysics.

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 the landing images, but an experiment to study the composition of local rocks may be a lost cause.

"But frankly, that experiment was a bonus and not really that important to the mission," he said.

- Renewed interest -

This month, US firm Astrobotic's Peregrine lunar lander began leaking fuel after takeoff, dooming its mission.

On Thursday, contact with the spaceship was lost over a remote area of the South Pacific after 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.

Russia, China and other countries from South Korea to the United Arab Emirates are also trying their luck to reach the Moon.

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".

To the Moon and back: modern lunar exploration
Tokyo (AFP) Jan 20, 2024 - Japan, whose unmanned "sniper" probe made a lunar touchdown on Saturday, is one of many countries and private companies launching new missions to the Moon.

The Smart Lander for Investigating Moon (SLIM) craft used precision technology to make a soft landing, although officials said its solar cells were not generating power.

The touchdown makes Japan only the fifth nation to land on the Moon, after the United States, the Soviet Union, China and India.

Modern lunar exploration programmes include plans to put humans on the Moon for the first time since 1972 and eventually establish bases there.

Here is a rundown of the latest moonshots:

- United States -

The first country to land on the Moon wants to build a sustained presence there as a pitstop for missions to Mars.

But it has faced two setbacks this month, as NASA postponed plans for crewed lunar missions and a private lander had to turn back after leaking fuel.

Under the US space agency's Artemis programme, astronauts had been due to fly around the Moon this year but the mission has been pushed back to 2025 to allow for extra safety checks.

A third Artemis voyage -- to put the first woman and first person of colour on lunar soil -- is now scheduled for 2026 instead of 2025.

Even that may be optimistic, because the Artemis 3 lander, a modified version of SpaceX's next-gen Starship rocket, has exploded in two test flights.

NASA says commercial tie-ups give it "more shots on goal" although its Peregrine lunar lander, made by US company Astrobotic, failed when it lost fuel after take-off.

The next attempt, by Texas-based Intuitive Machines, launches in February.

- India -

"India is on the Moon!" the country's space agency chair announced to cheers at mission control in August after Chandrayaan-3 became the first craft to land near the celestial body's south pole.

The unmanned mission orbited Earth several times to build up speed for its journey, resulting in a historic triumph for India's ambitious, cut-price space programme.

In 2014, India became the first Asian nation to orbit a probe around Mars, and Chandrayaan-3 followed a successful launch into lunar orbit in 2008 and a failed Moon landing in 2019.

The Indian Space Research Organisation (ISRO) has a dozen missions planned for 2024, including preparation for a three-day trip into Earth's orbit -- its first crewed space flight.

- Russia -

The Luna-25 mission in August was meant to mark Russia's return to independent lunar exploration, nearly half a century after the Soviet Union last landed on the Moon.

But the lander crashed on the rocky lunar surface, where it was meant to collect samples and analyse soil for one year.

The failure dealt a blow to Moscow's hopes of building on the legacy of the Soviet-era Luna missions, as financial troubles and corruption scandals plague its space programme.

President Vladimir Putin has also been working to strengthen space cooperation with China after ties with the West broke down following Russia's 2022 invasion of Ukraine.

- China -

The world's second-largest economy has pumped billions of dollars into its military-run space programme as China chases its "space dream" under President Xi Jinping.

A decade since the Chang'e-3 became the first Chinese spacecraft to land on the Moon, the country is now pursuing plans to send a crewed mission by 2030 and build a base there.

In 2019, the unmanned Chang'e-4 landed on the far side of the Moon, and a year later, Chang'e-5 brought the first lunar samples back to Earth in more than 40 years.

In October, the country sent a fresh team to its Tiangong space station in the latest crewed mission for the fast-growing space programme.

- Japan -

Japanese company ispace attempted a lunar landing in April last year but crashed, becoming the third private entity to have failed in the endeavour.

Space agency JAXA has suffered a run of bad luck, losing communication with its Omotenashi lunar probe carried on Artemis 1 in 2022.

It has also seen failures after lift-off of the next-generation H3 launch rocket and the normally reliable solid-fuel Epsilon rocket.

So hopes have been high for the success of its SLIM craft, nicknamed the "Moon Sniper" for its pin-point landing technology.

The mission will be closely studied by other countries from South Korea to the United Arab Emirates as they ramp up efforts to be the next to make lunar history.

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