JEFFREY KLUGER
And then there was one.
Since earlier this month, there had been something of a footrace in space, with India and Russia vying to be the first country to land a spacecraft in the moon’s south polar region.
On July 14, the Indian spacecraft, Chandrayaan-3, blasted off from the Satish Dhawan Space Center in southeastern India, carrying a 1,726 kg (3,805 lb) lander, which itself contains a little 26 kg (57 lb) rover. Then on Aug. 9, Russia followed in hot pursuit, launching its 1,750 kg (3,858 lb) Luna 25 lander from the newly built Vostochny Cosmodrome in the country’s far eastern Amur Oblast region.
On Aug. 23, India won the cosmic competition, setting Chandrayaan-3 down gently in the polar dust at 8:34 AM ET. “We have achieved a soft landing on the moon,” announced S. Somanath, the chairman of ISRO—the Indian Space Research Organization, to a packed mission control. “India is on the moon!”
“India’s successful moon mission is not just India’s alone,” added Prime Minister Narendra Modi in a live address to the control center and the nation. “This success belongs to all of humanity. And it will help moon missions by other countries in the future.” Moments later he expanded the celebration to X, (formerly Twitter), writing, “Historic day for India’s space sector. Congratulations to @isro for the remarkable success of Chandrayaan-3 mission.”
That India and Russia were in a race at all despite India’s 26-day head start was due to the fact that ISRO sent Chandrayaan-3 on a relatively leisurely five-week trajectory, making an ever-widening series of looping orbits around the Earth until it at last reached the the lunar vicinity, where it was captured by the moon’s gravity. Luna 25 was sent on a more direct path, one designed to get it to the moon in less than two weeks. Both ships were targeted for landing on or about Aug. 23.
But that was then. On Aug. 16, Luna 25 achieved lunar orbit; but on Aug. 20, it crashed into the moon’s surface, after an engine firing, intended to fine-tune its descent, went awry.
“At about 14:57 Moscow time, communication with the Luna-25 spacecraft was interrupted,” said Roscosmos, the Russian space agency, in a post on Telegram, translated by Google Translate. “According to the results of a preliminary analysis, [the spacecraft] switched to an off-design orbit and ceased to exist as a result of a collision with the lunar surface.” Even as heads bowed at Roscosmos, fists pumped at ISRO because that was the same day Chandrayaan-3 entered lunar orbit and posted images on X of the moon’s far side.
Modi wasn’t kidding when he said the landing was historic. Three other countries—the U.S., China, and the former Soviet Union—have also achieved soft lunar landings, but none has ever reached the south lunar pole, and that’s not for lack of trying. In 2019, Israel’s privately built and funded Beresheet spacecraft crashed after ground controllers lost touch with it when it was only 149 m (489 ft.) above the polar soil. In late April, a Japanese probe carrying a rover built by the United Arab Emirates came to ruin in the same region, when it too lost contact with Earth and went into a 4.8 km (3 mi.) death plunge before making impact with the surface.
The moon’s south pole is one of the harder places on the lunar surface to land because it is heavily boulder strewn, without the wide, flat expanses that the Apollo astronauts and early uncrewed landers targeted in the equatorial regions of the moon’s Earth-facing hemisphere. Of the spacecraft that have crashed in the south pole, none got close enough to try to negotiate the boulder fields. That ISRO was able to do so—briefly placing Chandrayaan-3 in hover mode when it was 850 m (2,800 ft.) above the surface while it looked for a clear parking spot—is a testament both to the nimbleness of the ship and the deft touch of the engineers in mission control.
Despite the hazards, there is good reason for the world’s space agencies and private space companies to continue targeting the south pole. Scientists had long believed that the lunar regolith—or soil—might be shot through with crystals of water ice. More significantly, there had been speculation that permanently shadowed craters in the south pole might effectively be frozen lakes. India’s Chandrayaan-1, launched in 2008, proved those theories correct. An on-board spectrometer confirmed the existence of the icy regolith, and a 29 kg (64 lb.) impactor probe dropped on the south pole proved the existence of water there too just before it hit.
For future astronauts hoping to settle the moon and live off the land, that matters a lot. Not only can ice be harvested for drinking water, the H20 molecule can be broken down to provide breathable oxygen, and the hydrogen and oxygen can be recombined to make rocket fuel. It’s for that reason that NASA’s Artemis program has targeted the south pole for its first crewed lunar landing sometime in the second half of this decade. China is aiming for the same region for its own crewed landing around 2030.
But boots on the moon are for later. For now, Chandrayaan-3 will get to work, using its suite of on-board instruments and its little six-wheeled rover to study a region of the moon that future explorers hope to call home.
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