Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news about interesting discoveries, scientific advances, and more.
CNN
—
The region of the moon at the center of the new international space race may be less hospitable than previously thought due to the possible presence of water ice, new research suggests. found.
Interest in the lunar south pole increased last year when India’s Chandrayaan-3 mission reached the lunar south pole for the first time. succeeded in soft landing In this region, a few days after the Russian Luna 25 spacecraft crashed On his way to attempting the same feat. NASA has selected the region as a landing site for the Artemis III mission, which could bring astronauts back to the moon as soon as possible. 2026, and also in china schedule To create future habitat there.
But now study A NASA-funded research institute is sounding the alarm. As the moon’s core gradually cools and shrinks, its surface wrinkles – like a grape shriveling into a raisin – which causes moonquakes and landslides that last for hours. Like other parts of the natural satellite’s surface, the region of Antarctica of much interest is prone to these seismic events, which could pose a threat to future human settlers and equipment.
“This is not to alarm anyone, and certainly not to discourage exploration of that part of the moon’s south pole,” said Thomas, lead author of the study and senior scientist emeritus at the National Air and Space Museum Earth Center. R. Watters said. “But it’s a warning that the moon is not a peaceful place with nothing going on.”
Over the past few million years, the moon’s circumference has shrunk by about 150 feet, researchers say. This is a significant number geologically speaking, but too small to cause any ripple effects on the Earth or its tidal cycles.
But on the moon, it’s a different story. Despite what its appearance suggests, the moon’s interior is still hot and therefore seismically active.
“There’s an outer core that’s melting and cooling,” Watters said. “As the moon cools, it shrinks, its internal volume changes, and the crust has to adapt to that change. This is a contraction of the entire planet, and tidal forces on the planet are also contributing to it.”
Because the moon’s surface is fragile, this pulling causes cracks, which geologists call faults. “People think of the moon as a geologically dead celestial body where nothing has happened to it for billions of years, but that couldn’t be further from the truth,” Watters said. “These faults are very young and things are ongoing. We actually detected landslides that occurred while the Lunar Reconnaissance spacecraft was in orbit around the moon.”
NASA’s Lunar Reconnaissance Orbiter (LRO) Released in 2009, which uses a variety of instruments to map the surface of the Moon. In the new study, published Jan. 25 in the Planetary Science Journal, Watters and his colleagues use data collected by the LRO to investigate the powerful Linked lunar earthquakes to a series of faults on the moon. Antarctic.
“During the Apollo earthquake experiment, four seismometers were in operation for about seven years, so we knew shallow lunar earthquakes existed, but we didn’t actually know what their epicenter was.” added Watters. “We also knew that the largest shallow lunar earthquake detected by the Apollo seismometer was near the South Pole. Trying to figure out what the source was is something of a detective story. As it turned out, these young flaws turned out to be the most likely suspects.”
The strongest earthquake recorded was equivalent to magnitude 5.0. On Earth, it would be moderate, but the moon’s lower gravity would make it worse, Watters said.
“On Earth, we have a much stronger gravitational force that sticks to the surface. On the Moon, it’s much smaller, so when you’re walking, just a little bit of ground acceleration can knock you off your feet,” he said. said. “That kind of shaking can actually start to throw things around in a low-G environment.”
Study co-author Lenny Weber, a planetary scientist at NASA, said the findings do not affect the landing site selection process for Artemis III, which depends on the scope and duration of the mission.
“It’s difficult to estimate exactly how often lunar earthquakes occur in a particular region, because, like earthquakes, lunar earthquakes are unpredictable,” Weber said. “Strong shallow lunar earthquakes are rare and pose a low risk to short-term missions on the lunar surface.”
NASA uses criteria such as whether it is safe to land in the area, the likelihood of achieving science goals, the availability of launch windows, and conditions such as terrain, communications, and lighting to determine which locations are located near the moon’s south pole. has identified potential landing areas for Artemis III, she added. . As part of the mission, the two astronauts will live and work on the lunar surface for about a week.
But Weber said that if humans were to stay on the moon for a long time, the site selection process might actually consider geographic features such as tectonic structure and proximity to topography.
Moonquakes could certainly be a problem for future human landing missions, says Professor Emeritus of geophysics at the University of Texas at Austin and researcher who first examined data collected by the Apollo Seismic Observatory. One of them, Yoshio Nakamura, said:
But Nakamura, who was not involved in the study, disagrees on the cause of the quakes and says data from the Apollo program shows the phenomenon is occurring tens of kilometers below the surface. Stated.
“We still don’t know what causes shallow lunar earthquakes, but it’s not a near-surface slip fault,” he said. “Whatever the cause of these earthquakes, they pose a potential threat to future landing missions, and we need more data about them.”
Whatever the underlying cause, the potential danger lunar quakes pose to astronauts means that, at least in the near future, humans will only be on the moon for a short period of time, at most a few days, Allen Hasker said. It is said that it will be limited by the fact that He is a research professor of geophysics at the California Institute of Technology, but was also not involved in the study.
“It’s very unlikely that a major lunar earthquake will occur during their stay. However, it’s good to know that these epicenters (which cause earthquakes) exist. They could be an opportunity to better study the moon, just as we do about the moon,” Hasker said. “By the time we have an actual lunar base, we should have a better understanding of the actual earthquake risks for future missions.”
Jeffrey Andrews Hanna, an associate professor of planetary science at the University of Arizona who was not involved in the study, has similar sentiments. “Moonquakes are a great tool for doing science,” he said in an email. “They’re like flashlights inside the moon, illuminating the moon’s structure so we can see it. Studying lunar earthquakes in the South Pole can reveal the moon’s internal structure and current activity. You can learn more about it.”