Fact Check: On the moon, exposed liquid water wouldn't freeze during the day but evaporate into vapor outside of craters

Fact-Check Article: "On the moon, exposed liquid water wouldn't freeze during the day but evaporate into vapor outside of craters"

What We Know

The claim that "on the moon, exposed liquid water wouldn't freeze during the day but evaporate into vapor outside of craters" touches on the behavior of water on the lunar surface, particularly in relation to temperature and sunlight exposure.

1. Temperature Conditions: The Moon has extreme temperature variations. During the lunar day, temperatures can reach up to 127°C (260°F) in sunlit areas, while at night, they can plummet to -173°C (-280°F) in shadowed regions. This stark contrast means that any liquid water exposed to sunlight would likely evaporate rather than freeze, as the temperatures are generally too high for freezing to occur in sunlit areas (NASA).

2. Presence of Water Ice: Research has confirmed the existence of water ice in permanently shadowed regions of the Moon, particularly within craters that do not receive sunlight. These areas maintain much lower temperatures, allowing water ice to accumulate and remain stable over time (Li et al., 2018). The study highlights that while water ice exists in these cold traps, the distribution of ice on the Moon is patchy and not uniformly spread across the surface.

3. Water in Sunlit Areas: Recent findings indicate that water molecules can also be found in sunlit areas of the Moon, albeit in much smaller quantities. These water molecules are thought to be embedded within the lunar regolith (the Moon's surface material) rather than existing as free liquid water (Smithsonian Magazine).

Analysis

The claim is partially true, as it accurately reflects the behavior of water under specific conditions on the Moon but overlooks important nuances:

• Evaporation vs. Freezing: The assertion that exposed liquid water would evaporate rather than freeze is supported by the extreme daytime temperatures on the Moon. In sunlit areas, the high temperatures would indeed lead to evaporation of any liquid water present. However, the claim does not clarify that liquid water is not typically found on the Moon's surface due to the lack of atmospheric pressure and the extreme conditions (Wikipedia).

• Permanently Shadowed Regions: The claim fails to mention that while liquid water would evaporate in sunlit areas, water ice can exist in permanently shadowed craters where temperatures are consistently low enough to prevent evaporation. This distinction is crucial, as it highlights that while liquid water is unlikely to remain stable on the surface, ice can persist in specific locations (Li et al., 2018).

• Source Reliability: The sources cited in this analysis are credible, including peer-reviewed studies and reputable scientific organizations. The research by Li et al. provides direct evidence of water ice on the Moon, while NASA's findings on lunar water are well-documented and widely accepted in the scientific community.

Conclusion

The verdict is Partially True. The claim accurately describes the behavior of water in sunlit areas of the Moon, where it would evaporate due to high temperatures. However, it overlooks the existence of water ice in permanently shadowed craters, which is a significant aspect of lunar water research. Thus, while the claim holds some truth, it lacks the full context necessary for a complete understanding of water's behavior on the Moon.

Sources

1. Direct evidence of surface exposed water ice in the lunar polar regions
2. Moon Water and Ices
3. Lunar water
4. Water-Ice Weathering in Permanently Shadowed Craters on the Moon
5. Direct evidence of surface exposed water ice in the lunar polar regions
6. The Moon Has More Water and Ice Hidden All Over Its Surface
7. Astrobiological Implications of Liquid Water IN The Moon!
8. Direct Evidence of Water Ice at Moon's Poles - Sky & Telescope