NASA's Amazing Moon Ice Discovery Protected on Lunar Surface by ‘Magnetic Anomalies’

Astronomers discovered the first evidence of water ice on the Moon in 2018. These areas are shielded from direct sunlight, but not from the solar wind, which is composed of charged particles emitted by the star. The lunar ice should have been destroyed, but this does not occur. Scientists are attempting to answer the question, "Why?"

However, the finding of water ice brought with it a new enigma. While these polar craters are insulated from direct sunlight, they are not protected from the solar wind, which is composed of charged particles that travel at hundreds of miles per second.

According to Paul Lucey, a planetary scientist at the University of Hawaii, this ionized wind is highly erosive and should have destroyed the moon's ice long ago. The moon, unlike Earth, no longer has a magnetic shield to buffer it from the brunt of these charged particles.

The finding of water ice, however, brought with it a new enigma. While these polar craters are insulated from direct sunlight, they are not protected against the solar wind, which consists of charged particles in the form of waves.

So how did the moon's polar ice survive?

Scientists from the University of Arizona presented their map of magnetic anomalies - areas of the lunar floor with unusually strong magnetic fields - sprinkled throughout the moon's south pole at the Lunar and Planetary Science Convention last month. These anomalies, discovered during the Apollo 15 and 16 missions in the 1970s, are thought to be remnants of the moon's historic magnetic defense, which NASA believes vanished billions of years ago.

The magnetic anomalies overlap with several massive polar craters that are always in shadow and are thought to contain historic ice deposits. According to the researchers, these anomalies could also act as tiny magnetic shields that protect lunar water ice from the constant bombardment of photovoltaic energy.

The authors compiled 12 regional maps of the lunar south pole previously captured by Japan's Kaguya probe during its 2007-2009 orbit of the moon. A magnetometer, capable of detecting pockets of magnetism across the lunar surface, was one of the spacecraft's science equipment.

Future lunar missions may shed light on the lunar south pole's pitch-black ice deposits. The Artemis missions, which will eventually return humans to the lunar surface for the first time since 1972, intend to land astronauts at the lunar south pole and set up a permanent base there. The study of the ice deposits in this area could reveal how they formed and why they have lasted so long.