New insights into the moon’s enigmatic magnetic field are emerging from the analysis of lunar rocks gathered by Apollo astronauts over 50 years ago, as scientists revealed. The upcoming retrieval of samples by astronauts in NASA’s Artemis program is anticipated to provide further revelations.
Four Artemis astronauts, including Canadian Jeremy Hansen, are set to embark on a pivotal test flight around the moon in the near future, aiming for a launch as early as April from Kennedy Space Center after facing delays. Their Artemis II moon rocket and Orion spacecraft, originally scheduled for February liftoff, were returned to NASA’s Vehicle Assembly Building for maintenance.
A study by researchers at the University of Oxford in England indicates that although the moon’s magnetic field was generally feeble throughout its history, there were intermittent periods three to four billion years ago when it intensified, surpassing Earth’s magnetic activity. These findings have been published in the journal Nature Geoscience.
Magnetic fields play a crucial role in shielding against cosmic rays and solar radiation, which is particularly vital for Earth’s protection.
The study revealed that the moon experienced brief but intense spikes in magnetic field strength that lasted up to 5,000 years, possibly even just a few decades, due to the melting of titanium-rich rocks deep within the lunar surface, as explained by lead author Claire Nichols.
Prior theories suggested sustained strong magnetic fields on the moon based on analyses of rocks collected during the Apollo missions from 1969 to 1972. With Artemis astronauts focusing on exploring the moon’s south polar region instead of the low-latitude lava plains of the Apollo era, the new samples are anticipated to shed more light on the moon’s ancient magnetic properties.
Nichols and her team reexamined previous measurements of the Apollo samples and discovered that elevated titanium levels correlated with evidence of heightened magnetic activity. Notably, rocks from both the first and last Apollo missions, Apollo 11 and Apollo 17, were rich in titanium.
“We have uncovered a crucial connection,” Nichols stated in an email.
The researchers highlighted that magnetic field activity on the moon could be sporadically intense and more variable than previously assumed.
The researchers argue that the Apollo samples may not be fully representative of the moon’s overall composition, as they were collected from areas abundant in titanium that were pushed to the surface through volcanic activities.
Future Artemis missions plan to investigate ancient rocks near the moon’s south pole, where shadowed craters are believed to harbor water ice.
Understanding the moon’s magnetic shield history is crucial for evaluating planetary habitability, according to Nichols.