Is there water on the moon, and how it could form has long been debated. In a new study, scientists have revealed a map of the moon’s water near the south pole.
Scientists used the now-retired Stratospheric Observatory for Infrared Astronomy (SOFIA) to compile the first detailed, expansive map of water distribution on the moon near the south pole. The map covers about 1/4 of the surface of the moon near -60° latitude with a resolution of 5 km. Using this map, scientists were able to determine how water relates to surface features on the moon, stay away from sunlight and prefer cold regions.
The study offers hints about how water may move around the lunar surface, particularly near the south pole — a critical region for space exploration — with clear, recognizable lunar features highlighted by the water data.
Bill Reach, director of the SOFIA Science Center at NASA’s Ames Research Center in California’s Silicon Valley and lead author of the study, said: “When we look at the water data, we can see crater rims, we can see the individual mountains, and we can even see differences between the day and night sides of the mountains, due to the higher water concentration in these places.”
The volume and distribution of water on the moon’s sunlit surface are tracked by this most recent SOFIA observation, along with two other findings. Previous missions that observed large areas of the lunar surface looked at different wavelengths of light that failed to distinguish water from related compounds such as hydroxyl. The moon’s water can be found in the soil as ice crystals or as water molecules chemically bonded to other substances.
The data collected at the south pole of the moon was compared to a relatively dry reference area close to the equator to observe how the abundance changed rather than determine the exact amount of water in the area. Similar to how skiers on Earth are aware that slopes that receive less direct sunlight hold snow longer, the water was discovered in greater concentrations on the shadow sides of craters and mountains. This indicates that the lunar local geography has a significant impact on its water content.
Casey Honniball, a visiting assistant researcher and VIPER science team member at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, said: “With this map of SOFIA data, and others to come, we’re looking at how water is concentrated under different environmental conditions on the Moon. This map will provide valuable information to the Artemis program about potential prospecting areas and a regional context for future science missions. , such as VIPER.”
- William T. Reach, Paul G. Lucey et al. The distribution of molecular water in the lunar southern polar region based on 6 μm spectroscopic imaging. The journal Planetary Science. DOI: 10.3847/PSJ/acbdf2