Space agencies and companies are aiming to travel deeper into the <a href="https://www.thenationalnews.com/future/space/2024/05/25/how-studying-climate-patterns-in-distant-worlds-can-help-in-the-search-for-alien-life/" target="_blank">solar system</a>, making the Moon a vital base for testing new technology, studying living conditions in space and preparing for future missions. The renewed interest in lunar exploration is fuelled by a collaboration between government bodies such as Nasa and private-sector companies including <a href="https://www.thenationalnews.com/future/space/2024/05/15/elon-musks-spacex-prepares-starship-for-next-test-flight-in-3-to-5-weeks/" target="_blank">SpaceX</a> and <a href="https://www.thenationalnews.com/future/space/2024/05/15/meet-blue-origins-first-space-tourism-passengers-since-explosion-last-year/" target="_blank">Blue Origin</a>, as well as <a href="https://www.thenationalnews.com/future/space/2024/04/30/change-6-china-to-launch-mission-that-will-return-soil-samples-from-moons-dark-side/" target="_blank">China</a>, which is developing its own lunar research station. Dr Dimitra Atri<b>,</b> an astrophysicist at New York University Abu Dhabi, said the Moon could eventually become a refuelling station for Mars-bound missions. "Harnessing the water on the Moon to produce oxygen and hydrogen, essential components of rocket fuel, holds the potential to transform lunar mining operations into a 'gas station' for future space missions," he said. "The idea is that by converting water into these propellants, the Moon could serve as a launching point for spacecraft, offering a cost-effective alternative due to its lower gravity." But several challenges would first have to be addressed, including scarcity of energy resources, limited availability of water and the absence of a protective atmosphere, as well as extreme temperatures. Dr Atri said more innovative solutions were needed to make current technology resilient to harsh lunar conditions, where temperatures near the equator can reach 121°C in daylight and plummet to minus 133°C at night. The concept of using materials already available on the Moon is described as "in-situ resource utilisation" (ISRU) by scientists and engineers, and is now being used as a key strategy for sending humans to the lunar surface and then launching them into deep space. Apart from using the water to produce oxygen and hydrogen for rocket fuel, it could also be converted for astronauts to drink. Rockets taking off from the Moon would also require less fuel because it has lower gravity compared to Earth, significantly reducing the cost and complexity of missions bound for the deeper solar system. Dr Nidhal Guessoum, an astrophysicist at the American University of Sharjah, said the long-term projects currently being planned would be "impossible" without ISRU. "It would mean bringing from Earth all the resources and supplies needed for any human activity on the Moon or Mars," he said. "The main issue is the scalability of the extraction [from surface and underground materials), transformation and utilisation (energy production, manufacturing, human consumption]." Aiming for crewed deep-space missions would also help create a cis-lunar economy – the economic activities taking place in the space between the Earth and the Moon's orbit – including satellite operations and lunar resource extraction. A PwC lunar market assessment report in 2021 found the lunar economy could exceed a value of $154 billion by 2040. Driving factors would include transporting human resources between the Moon and Earth, using lunar data on Earth for mission preparation and research, and resource utilisation. "In the medium to long term [the next few decades], the development of a cis-lunar economy holds great promise for both space agencies and the private sector, which should work together to cut costs and benefit from each other’s expertise and capabilities [for example, new, more efficient rockets, lunar infrastructure, exploration and research]," said Dr Guessoum. "For economic purposes, activities on and around the Moon will focus on extracting water, Earth-rare minerals and construction materials. "Private companies can provide services, ranging from transportation to, on and from the Moon, to construction, manufacturing, infrastructure, food production and recycling. And lastly, tourism and exploration will probably start slowly but then boom in a few decades." Another benefit that space agencies see with lunar missions is the scientific insight that can be gained from landing humans on the surface again. Sending humans there for long term, compared to only seven to 22 hours during the Apollo era, would advance scientific understanding of the Earth, Moon and the broader solar system. "First, we learn about the Moon, its past and present, how it formed [some information can be extracted from its rocks and geology], and how it has affected our planet during our common history," said Dr Guessoum. "On the Moon and in the space between us, studying space radiation is crucial, both for satellites and spacecraft and for human presence and travel in space. "We also need to find water and important minerals and chemical elements [helium and lithium] for bases on the Moon and for travel to Mars [water, to be broken into hydrogen and oxygen] is the fuel for rockets and spacecraft to Mars or asteroids [for mining]."