Explainer | Why countries are vying for moon dust

In 1969, 12 Americans landed on the moon and for the first time in human history, humans set foot on an extra-terrestrial body. 1972 saw the last crewed lunar mission, then US President Richard Nixon said that the mission might as well be the last time humans set foot on the moon the 20th century. The mission then was surrounded by a vigorous space race between Cold War rivals, the USSR and the United States.

US’s public space agency NASA, China’s China National Space Administration and Japan, Russia and the UK either missions planned over the next few years or have ongoing scientific missions on the moon involving lunar rovers to study the surface of the moon, presence of water among other things and strangely, Lunar dust. The UAE is scheduled to land a rover on the moon in 2024.

The US has struck deals with four private companies to collect soil and dust from the moon. In one of the contracts, NASA will pay just one dollar to private space company Lunar Output for lunar dust. Chinese space Agency China National Space Administration’s (CNSA) Chang’e 5 mission has finished collecting rocks and lunar dust and is in a sealed package headed back to Earth at the moment.

If the samples safely arrive on Earth (expected to happen around mid-December), China would only be the third nation after the US and the former Soviet Union to have gathered samples from the moon and the first to have done so in the 21st century. US’s Apollo program over six mission brought back about 382 kg of lunar rocks and dust, whilst the USSR brought back a mere 300 grams of samples from the moon over three missions. China’s lander has drilled as deep as 2 metres for cores of rocks and has collected about 3 kg of samples from the moon.

So, why are countries gathering lunar dust?

China and US have kept reasons for gathering lunar dust and rocks under wraps, but most likely, these are being gathered for one major reason. Lunar dust and rocks in the past, have caused a lot of potentially dangerous issues for moon missions and have proven hazardous. Countries aim to gather moon dust to study it, in an attempt to mitigate its effects.

Five decades ago, when American astronauts landed on the moon and returned to Earth, one of their prime complaints was that of lunar dust getting everywhere. Lunar dust unlike regular household dust is very sticky and abrasive, which means, it got on to the visors of the astronaut’s helmets, scratching and damaging them. It also led to damaging seals on pressure suits, leading to a potential leak of air in the suit, irritating eyes, getting into crevices of the spacecraft and into pores of astronauts’ skin. Apollo 17 mission’s Gene Cernan had said after his last moonwalk, “I ain't going to do much more dusting after I leave here. Ever.” This gives us an indication of how much moon dust not only got on to astronauts’ skins, but also on their nerves.

Lunar dust has been so hard to get rid of too that vacuum cleaners, brushes, wet cloths and many other attempted solutions didn’t help. 50 years on, NASA hasn’t been able to find a comprehensive solution to get rid of lunar dust or to avoid it.

Australian physicist Brian O’Brien, a leading expert on lunar dust who earlier worked with NASA on a related experiment, had put forward an explanation for why lunar dust is as sticky as it is. According to O'Brien, electrostatic charge of the dust is the major source of its stickiness and it changes when the sun is high and UV radiation is at its highest. Lunar dust happens to be more charged and thus more sticky, whch is why when the sun goes down, lunar dust isn’t as adhesive, he states.

Other scientists have posited theories on various aspects of lunar dust over the past few decades. However, debates on why they are sticky, abrasive, dangerous and downright irritating still shroud the moon dust mystery. It is also likely that lunar dust could lead to other discoveries about the moon.