It's almost 50 years since we last set foot on the Moon – so what's behind the rush to get back?

For centuries, humans have produced books, paintings, poems, and one famous Pink Floyd album about the mysterious “dark side” of the Moon
For centuries, humans have produced books, paintings, poems, and one famous Pink Floyd album about the mysterious “dark side” of the Moon

Those old enough to remember it describe the events of July 20 1969 as a moment of near-incomparable excitement, as a 38-year-old Neil Armstrong became the first human to step on to the Moon’s cratered surface, followed by co-engineer Buzz Aldrin. A further 10 astronauts walked on the Moon in the following three years, all of them American.

Then, interest quickly waned: since 1972, nobody has returned. The American flag planted by Armstrong on that first visit is probably still there, think scientists – there’s just nobody around to see it.

But now, the Earth’s satellite seems to be going through something of a renaissance. Exuberant from his space flight last week, Amazon founder Jeff Bezos, the world’s wealthiest individual, offered to cover up to $2bn (£1.4bn) of Nasa costs if the US space agency awarded his company, Blue Origin, a contract to make a spacecraft designed to land astronauts back on the moon. It comes three months after his company lost a key Nasa moon-landing contract to SpaceX, the rival firm owned by Tesla founder Elon Musk, the world’s second wealthiest individual.

It sounds, to many, like the latest skirmish in the new billionaire space race – private entrepreneurs competing to make money from extra-terrestrial travel (and perhaps looking to boost their personal prestige too). But scientists say the Moon, often overlooked, still offers impressive scientific and economic benefits to humanity. So what exactly are they?

Shedding light on the universe

In the run-up to the launch of Apollo 11 in 1969, while training in Hawaii, astronauts Armstrong, Aldrin, and Michael Collins were given lessons in geology, plus the mysterious science of “moon rocks”. It spoke to a belief among astronomers that a better understanding of the Moon’s physical make-up could provide important clues for our broader understanding of the universe.

That belief persists, says Prof Andrew Coates, deputy director of the Mullard Space Science Laboratory at University College London - and now better technology means we could potentially learn even more. Scientists are most interested in the composition of the South Pole-Aitken Basin which, at 2,500km wide and 13km deep, is the oldest and deepest basin area on the Moon and probably a remnant of a collision which occurred early in the solar system’s history.

“Looking at cratering density, assuming that things are flying around at about the same frequency in different parts of the solar system, you can use that to model the ages of different terrain on the surface of other bodies [like other planets],” says Prof Coates. “That gives you a good picture of how their solar system was formed.”

Astronauts could also conduct space weather experiments, attempting to track weather events that are heading towards Earth.

Radio silence

For centuries, humans have produced books, paintings, poems, and one famous Pink Floyd album about the mysterious “dark side” of the Moon, the half that is not visible from Earth (known by scientists as the “far side”).

But the rugged, unexplored area also provides a scientific opportunity. Radio astronomy (using radio waves to explore the solar system) is famously difficult on Earth due to signal interference; something as simple as a microwave next door can throw a spanner into the works, says Prof Coates. But this problem does not apply on the Moon’s far side, which is unaffected by the Earth’s radio signals.

“I personally think one of the most exciting reasons to go back to the Moon is to set up telescopes and observatories on the far side,” says Affelia Wibisono, a PhD researcher at the Mullard Space Science Laboratory. “Radio telescopes would be able to detect the very faint signals left by the Big Bang that would tell us what the universe was like during the very early stages of its formation.” An “added bonus”, says Wibisino, is that the Moon “does not have an atmosphere,” meaning “optical telescopes would be able to take breathtakingly clear images, something that we could never do here on Earth.”

Mineral rush

Our natural satellite contains a number of precious minerals that could, some think, deliver large profits to companies and governments back on Earth. On the Moon sits large quantities of the rare element Helium-3, which is useful for nuclear fusion – an attempt to replicate the energy-generating processes of the Sun on Earth. It also holds rare earth metals, which are used in modern electronic devices like smartphones, computers, and medical equipment.

The metals are particularly important to the economy of China, which makes 75 percent of the world’s mobile phones and 90 percent of its computers, according to Bloomberg. This might, some analysts think, explain China’s recent lunar ambitions; in 2019, the Chinese space agency became the first to land a probe on the far side of the Moon.

Environmentalists are horrified by the prospect of plundering the Moon for its resources. But former Nasa Administrator Jim Bridenstine predicted in 2019 that private companies will begin harvesting rare metals from the Moon at some point this century. “There could be tons and tons of platinum group metals on the moon, rare-earth metals, which are tremendously valuable on Earth,” he told American broadcaster CNBC, praising the likes of Bezos, Musk, and Branson for their contributions.

But a lunar mineral rush could create conflict back on Earth. As of yet, there is still no sturdy international blueprint for how moon resources would be allocated, beyond a 1967 United Nations treaty which said that no nation can claim ownership over the Moon. Some fear a politically messy and potentially violent geopolitical situation, akin to the rush for land in the 19th century Wild West.

Questions also remain about whether the mining would prove commercially viable. “People have wondered about mining the Moon for Helium-3, but that seems not to be cost effective,” says Prof Coates. “It would be useful for nuclear fusion, but unfortunately we haven’t got fusion going yet on Earth. And getting [those resources] back to Earth seems like a very costly prospect."

A stop-off to Mars

In 2004, US President George W. Bush promised to return humans to the Moon by the year 2020 and to use that as a jumping-off point, or “stepping-stone”, for a more ambitious venture to Mars. Readers will know that the first part of that plan failed to materialise – 2020 came and went without any humans stepping back on the rock. But the second part of Bush’s promise – the notion of a lunar “stepping stone” – has persisted.

The issue with using the Moon as a launch pad is gravity, says Prof Coates. The Moon has only about one-sixth the gravity of Earth, but that’s still enough to make it difficult to launch a rocket directly from the lunar surface. Instead, attention in the space community has now turned towards the idea of a “lunar gateway”: a mini space station in constant orbit around the Moon. This is the centerpiece of Nasa’s strategy, signed by President Donald Trump in 2017.

Built with the help of more than a dozen other nations, the lunar gateway would weigh about 75 ton, Nasa predicts, consisting of just one or two modules, each roughly the size of a bus – making it much smaller than the existing space station, which orbits the Earth. Astronauts could live aboard the gateway for six weeks; from there, they could make trips to the lunar surface with the help of reusable landing craft.

A long-term presence in orbit around the Moon would help scientists test the science and technology they would need to reach Mars. The Moon is also a source of water and rocket fuel, thanks to ice deposited in its poles. Mars-bound astronauts could stop off at the Moon and pick up these supplies, before continuing to their final destination, eliminating the huge burden of having to lift those materials off Earth.

What do you think about the sudden rush to return to the moon? Let us know in the comments section below.