The prevailing theory now, is that positively charged hydrogen ions propelled by the solar wind bombard the lunar surface and spontaneously react to make water (as hydroxyl (OH-) and molecular (H2O)). However, a new multinational study published in Astrophysical Journal Letters proposes that solar wind may not be the only source of water-forming ions.
The researchers show that particles from Earth can seed the moon with water, as well, implying that other planets could also contribute water to their satellites. It was previously assumed that water was incorporated into these objects during the formation of the solar system, but there is growing evidence that water in space is far more dynamic. Though the solar wind is a likely source for lunar surface water, computer models predict that up to half of it should evaporate and disappear at high-latitude regions during the approximately three days of the full moon when it passes within Earth's magnetosphere. The latest analysis of surface hydroxyl/water surface maps by the Chandrayaan-1 satellite's Moon Mineralogy Mapper (M3) showed that lunar surface water does not disappear during this magnetosphere shielding period.
Earth's magnetic field was thought to block the solar wind from reaching the moon so that water could not be regenerated faster than it was lost, but the researchers found this was not the case. By comparing a time series of water surface maps before, during and after the magnetosphere transit, the researchers argue that lunar water could be replenished by flows of magnetospheric ions, also known as "Earth wind." The presence of these Earth-derived ions near the moon was confirmed by the Kaguya satellite, while THEMIS-ARTEMIS satellite observations were used to profile the distinctive features of ions in the solar wind versus those within the magnetosphere Earth wind.
Previous Kaguya satellite observations during the full moon detected high concentrations of oxygen isotopes that leaked out of Earth's ozone layer and embedded in lunar soil, along with an abundance of hydrogen ions in our planet's vast extended atmosphere, known as the exosphere. These combined flows of magnetosphere particles are fundamentally different from those in the solar wind. Thus, the latest detection of surface water in this study refutes the shielding hypothesis and instead suggest that the magnetosphere itself creates a "water bridge" that can replenish the moon.
Read More: https://phys.org/news/2021-01-evidence-lunar-surface-earth-magnetosphere.html
The researchers show that particles from Earth can seed the moon with water, as well, implying that other planets could also contribute water to their satellites. It was previously assumed that water was incorporated into these objects during the formation of the solar system, but there is growing evidence that water in space is far more dynamic. Though the solar wind is a likely source for lunar surface water, computer models predict that up to half of it should evaporate and disappear at high-latitude regions during the approximately three days of the full moon when it passes within Earth's magnetosphere. The latest analysis of surface hydroxyl/water surface maps by the Chandrayaan-1 satellite's Moon Mineralogy Mapper (M3) showed that lunar surface water does not disappear during this magnetosphere shielding period.
Earth's magnetic field was thought to block the solar wind from reaching the moon so that water could not be regenerated faster than it was lost, but the researchers found this was not the case. By comparing a time series of water surface maps before, during and after the magnetosphere transit, the researchers argue that lunar water could be replenished by flows of magnetospheric ions, also known as "Earth wind." The presence of these Earth-derived ions near the moon was confirmed by the Kaguya satellite, while THEMIS-ARTEMIS satellite observations were used to profile the distinctive features of ions in the solar wind versus those within the magnetosphere Earth wind.
Previous Kaguya satellite observations during the full moon detected high concentrations of oxygen isotopes that leaked out of Earth's ozone layer and embedded in lunar soil, along with an abundance of hydrogen ions in our planet's vast extended atmosphere, known as the exosphere. These combined flows of magnetosphere particles are fundamentally different from those in the solar wind. Thus, the latest detection of surface water in this study refutes the shielding hypothesis and instead suggest that the magnetosphere itself creates a "water bridge" that can replenish the moon.
Read More: https://phys.org/news/2021-01-evidence-lunar-surface-earth-magnetosphere.html
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