Astronomers at Auburn University have discovered that the third discovered interstellar visitor, 3I/ATLAS, has a significantly higher water content than other comets in our solar system. Using data from the Ultraviolet / Optical Telescope on the Neil Gehrels-Swift Observatory, researchers detected strong OH emissions, which are typically not seen at such great distances from the Sun.
The team observed 3I/ATLAS about a month after its discovery and found that around 20% of its surface is actively producing water vapor, far exceeding the typical 3-5% for comets in our solar system. This suggests that 3I/ATLAS may be visiting a star for the first time, resulting in an unusually high amount of water to expel.
The researchers have proposed two hypotheses based on this observation: one that the comet’s water production peaks near perihelion and another that it drops significantly after perihelion. If confirmed, these findings could indicate whether 3I/ATLAS originated from a low- or high-metallicity system, providing valuable insights into its origins.
With close observations planned for the coming months, scientists will have the opportunity to test new hypotheses and further understand the composition of this unique interstellar visitor.
Source: https://www.universetoday.com/articles/3iatlas-is-very-actively-releasing-water