Going through a phase
What accounts for our current obsession with the moon? We’ve found evidence of water in sunlit spots, got new views of the ‘dark side’. Amid growing interest in its rare minerals, there are plans for humans to return. How close are we to permanent bases?
It’s hard to believe that only 12 men have walked on the moon, all of them Americans, and the last of those all the way back in 1972. Once the space race between the US and USSR ended, the world seemed to just turn away from it all. Major missions have focused on Mars and the Sun; so has popular culture. Earth’s core has had more of a starring role in Hollywood than our steadfast satellite. But for the scientific community, the promise that the moon holds has never been greater. This naked rock devoid of atmosphere, rotating in time with Earth, about 1.3 light seconds away, is a vital stepping stone for interplanetary exploration. It also holds rare minerals and elements, including stores of titanium and helium-3 that could be used to power nuclear fusion plants. And it holds frozen water.
The new space race is a more quiet but equally frenetic one focused on who can first figure out how to get at these precious resources, and transport them home, or find ways to build around them on the lunar surface.
“We explore space because we are curious beings,” says Anil Bhardwaj, astrophysicist, planetary scientist, and director of the Physical Research Laboratory, Ahmedabad, a unit of the government’s Department of Space and a national space research institute. “We also explore as an insurance policy for humanity, which can be wiped out at any second if a large enough asteroid collides with Earth, as happened with the dinosaurs. We explore because everyone else is exploring and it’s important for us to make our mark. But we also explore because ultimately it all boils down to economics. Whoever manages to bring back these elements, it could generate billions of dollars for them.”
This year, accordingly, will be a very busy one on the moon. At least five missions aim to land there in 2023. Japanese startup ispace aims to have a lander on the moon in April. In June, India is scheduled to launch Chandrayaan-3, equipped with a lander and rover. The private American aerospace companies Intuitive Machines and Astrobotic Technology each aim to place a lander there. And Russia’s lander mission Luna 25 (its first such mission since Luna 24 in 1976) is scheduled for launch in July.
Humans are headed back there too. The Artemis programme of the US National Aeronautics and Space Administration (NASA) plans to send a crewed craft to the moon by 2025. China’s National Space Administration aims to do this by 2030.
A lot of the attention is now focused on the permanently shadowed regions of the moon’s south pole, where temperatures stand below -200 degrees Celsius, and India is part of the reason for this. In 2008, NASA instruments aboard the Indian Space Research Organisation’s first moon mission, the Chandrayaan-1 orbiter, definitively confirmed the presence of water ice on the moon.
“At first we weren’t convinced about the data we were receiving,” says Bhardwaj. “No one expected water to show up like that, so prominent and evident.” Amid tremendous excitement, NASA turned the lenses on its Deep Impact and Cassini spacecraft towards the moon for a closer look, and confirmed the findings.
Water is a dramatic game-changer, of course. It indicates potential for life, for research stations or settlements, perhaps even crops. Already lunar soil has been used to germinate plants on Earth.
With the diameter of the moon being about onefourth that of Earth, that’s a lot of potential.
If Chandrayaan-3 succeeds, India could become only the fourth country in the world to place a lander on the moon. After the US and Russia, China’s Chang-e missions have placed landers and rovers there, three times between 2013 and 2020. As Chandrayaan-3 readies to study thermal conductivity and seismic activity, among other things, lingering mysteries remain: Why is there rust on the moon, even though it has no ambient oxygen; and why exactly is the moon’s crust 20 km thicker on the far side?
Some leaps of discovery have recently been made from here on Earth. Read on for a closer look.
A LOT OF THE ATTENTION NOW FOCUSED ON THE MOON IS AIMED AT ITS SOUTH POLE, WHERE TEMPERATURES STAND BELOW -200 DEGREES CELSIUS, AND THERE IS NOW DEFINITIVE PROOF OF WATER ICE