A new study by NASA has found that the water on Comet 67P/Churyumov–Gerasimenko has a molecular signature closely matching that of water found in Earth’s oceans, reviving the possibility that Jupiter-family comets like 67P played a role in supplying water to our planet.
Researchers have long debated how Earth became abundant in liquid water. While volcanic activity is thought to be responsible for producing some of Earth’s water, evidence suggests that icy bodies like asteroids and possibly comets collided with our planet during the early years of the solar system, delivering significant amounts of water.
The connection between asteroid water and Earth’s oceans is generally well-supported, but the role of comets has remained uncertain. Previous measurements of Jupiter-family comets revealed a strong link between their water and Earth’s based on a crucial molecular signature – the ratio of deuterium to regular hydrogen found in water.
Comet 67P contains higher levels of deuterium than expected, leading some scientists to question its connection to Earth’s water. However, a new study led by NASA planetary scientist Kathleen Mandt has reevaluated this theory.
Mandt’s team analyzed over 16,000 measurements taken by the European Space Agency’s Rosetta mission and found that there is a correlation between deuterium measurements and the amount of dust in the comet’s coma. This suggests that some measurements may have been misleadingly high due to dust surrounding the comet.
When dust reaches the outer coma and dries out, it allows for accurate measurement of the comet’s true deuterium content. These findings could significantly impact our understanding of the origins of Earth’s water and how comets contribute to this vital resource.
The study may reopen discussions about the role of comets in Earth’s water history and provide new insights into the delivery of water to our planet, potentially supporting a comet-driven origin for some of Earth’s oceans.
Source: https://www.yahoo.com/news/jupiter-comet-water-matches-earth-230917928.html