Cape Canaveral, Florida – lunar Rocks collected by Apollo astronauts New discoveries dating back more than half a century provide new insight into the moon’s mysterious magnetic field, scientists reported Wednesday.
Samples that will be retrieved by future lunar astronauts NASA’s new Artemis program That should yield more clues. Four Artemis astronauts are expected to fly around the Moon on a mission A decisive test flightwill lift off early in April from Kennedy Space Center after weeks of delay.
The study, conducted by researchers from the University of Oxford in England, suggests that although the Moon’s magnetic field was weak during most of its existence, it enhanced and even exceeded Earth’s magnetic activity during very short periods 3 to 4 billion years ago. Their findings appear in the journal Nature Geoscience.
Magnetic fields help protect against dangerous cosmic rays and, in the case of Earth, from harsh solar radiation as well.
Lead author Claire Nicholls said the moon has “incredibly short spikes in high magnetic field strength” lasting no more than 5,000 years and perhaps as short as a few decades, the result of the melting of titanium-rich rocks deep within the moon.
Scientists previously assumed that the lunar magnetic field remained strong for long periods based on their analysis of rocks brought back by Apollo astronauts from 1969 to 1972. With the Artemis astronauts exploring the Moon’s south polar region rather than the low-latitude lava plains of Apollo’s days, the new samples should shed more light on the Moon’s ancient magnetism.
Nichols and her team studied previous measurements of Apollo samples and found that high titanium levels correspond to preserved traces of high magnetic activity. Rocks from the first and last moon landings — Apollo 11 and Apollo 17 — were loaded with titanium.
“We have found the missing link,” Nichols said in an email. Magnetic field activity “can be intermittently very strong and may fluctuate much more than we traditionally thought.”
The researchers believe that the Apollo samples do not represent what was found on the moon because they came from similar sites where titanium is abundant, after it was pushed to the surface through volcanic eruptions. Future Artemis astronauts plan to study ancient rocks near the South Pole where permanently shadowed craters are thought to contain water ice.
Understanding the history of the Moon’s magnetic shield is “critical to thinking about the habitability of planets,” Nichols said.
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