The race to reveal the mysteries of the dark side of the Moon – 08/22/2023 – Science

The Sun remains just above or just below the horizon, while tall mountains cast dark shadows.

Deep craters guard a darkness that seems eternal. Some of these areas have been shielded from sunlight for billions of years.

In these regions, temperatures reach an astonishing -248º C, because the Moon has no atmosphere to heat the surface.

Until now, no human being has set foot in this completely unexplored world.

The south pole of the Moon, according to NASA (American space agency), is intriguing and full of “mystery and science”.

No wonder there is a “space race” to reach this point in the south of the Moon, far from the landing sites of manned missions that visited the satellite a few decades ago, clustered around the equator.

This week, India plans to land a Chandrayaan-3 robotic probe near the South Pole.

On Sunday, Russia’s Luna-25, which was supposed to be the first vehicle to do this, crashed into the Moon.

It was Russia’s first lunar mission in nearly 50 years.

Preliminary information showed the 800 kg probe “ceased to exist as a result of a collision with the surface of the Moon,” Russia said in a statement.

India is also planning a joint Lunar Polar Exploration (Lupex) mission with Japan to explore the shadowed regions or the so-called “dark side of the Moon” by 2026.

Why is the South Pole emerging as an attractive scientific destination? Scientists say that one of the main reasons is water.

Data collected by the Lunar Reconnaissance Orbiter, a NASA spacecraft that has been orbiting the Moon for 14 years, suggest that water ice is present in some of the large, permanently shadowed craters that could potentially support life.

Water exists as a solid or vapor on the Moon because of the vacuum — the Moon doesn’t have enough gravity to maintain an atmosphere.

India’s Chandrayaan-1 lunar mission was the first to find evidence of water on the Moon, in 2008.

the history of water

“It has not yet been proven that water ice is accessible or manipulable. In other words, are there water reserves that can be extracted economically?”, asks Clive Neal, professor of planetary geology at the University of Notre Dame, in the United States.

The prospect of finding water on the Moon is exciting in many ways, according to scientists.

Frozen water uncontaminated by the Sun’s radiation may have accumulated in cold polar regions over millions of years, leading to the accumulation of ice at or near the surface.

This provides a unique window for scientists to analyze and understand the history of water in our solar system.

“We can address questions such as where did water come from and when, and what are the implications for the evolution of life on Earth,” says Simeon Barber, a scientist at The Open University in the UK who also works at the European Space Agency.

There are other “pragmatic” reasons for accessing water on the Moon’s surface or just below it, says Professor Barber.

Many countries are planning new human missions to the moon, and astronauts will need clean water and sanitation.

Transporting equipment from Earth to the Moon involves overcoming Earth’s gravitational pull.

The larger the equipment, the more propellants and fuel payload would be needed to achieve a successful moon landing.

New commercial space companies charge around $1 million (£1.9 million) to get a kilogram of payload to the moon.

“It’s $1 million per gallon of fresh water. Space entrepreneurs undoubtedly see lunar ice as an opportunity to provide astronauts with locally sourced water,” says Barber.

But that is not all.

Water molecules can be broken down into hydrogen and oxygen atoms, and both can be used as propellants to fire rockets.

But first scientists need to know how much ice there is on the moon, in what forms and whether it can be efficiently mined and purified to make it safe to drink.

Furthermore, some points at the south pole are bathed in sunlight for extended periods of time, up to 200 Earth days of constant illumination.

“Solar energy is another resource [para estabelecer uma base lunar e equipamentos de energia] potential that the pole has,” says Noah Petro, NASA project scientist.

The lunar south pole also sits on the rim of a massive impact crater.

With a diameter of 2,500 km and reaching depths of up to 8 km, this crater is one of the oldest formations in the solar system.

“By landing at the pole, you can start to understand what’s going on with this big crater,” says Petro.

Navigating the lunar pole with spacesuits and sampling tools in a distinctly different light and temperature environment in contrast to previously explored equatorial locations also promises to provide valuable insights.

But scientists are wary of calling what’s happening a “race to the south pole”.

“These missions have been planned for decades and have been delayed many times. The race is not critical to our understanding of the Moon. The last time there was a real space race, we ended up losing interest in the Moon after three years and not returning to its surface.” in 50 years,” says Vishnu Reddy, professor of planetary science at the University of Arizona.

The Indian and Russian missions also had some common goals, the scientists point out.

Both intended to land similarly sized spacecraft in the south polar region, further south of the equator than any previous lunar mission.

After an unsuccessful landing attempt in 2019, India will look to showcase its precision moon landing capability near the pole.

It also aims to examine the Moon’s exosphere — an extremely sparse atmosphere — and analyze polar regolith, an accumulation of loose particles and dust accumulated over billions of years that rest on a bedrock.

Luna-25’s objectives included analysis of the composition of the polar regolith, as well as an examination of plasma and dust elements from the lunar pole’s exosphere.

To be sure, the Indian orbiter’s landing site is “a bit far from the actual pole”.

“But the data [que ele vai fornecer] will be fascinating,” says Professor Neal.

Russia and China have plans to build a lunar space station to develop research facilities on the satellite’s surface, in orbit, or both.

Russia is planning more Luna missions.

NASA is sending instruments on commercial landers to go to places beyond the moon.

Japan is preparing to send an intelligent lander (the SLIM mission) on Aug. 26 — a small-scale mission to demonstrate precise lunar landing techniques by a small rover.

And, of course, NASA’s Artemis program aims to take astronauts back to the Moon in a series of spaceflights, more than half a century after the last Apollo mission.

“The Moon is like a giant jigsaw puzzle. We have some of the pieces, corners and edges based on lunar meteorite samples and data. We have a picture of what the Moon looks like, but that picture is incomplete,” Petro said. “The Moon is still surprising us.”