Overview
- University of Michigan researchers report in Nature Astronomy that 3I/ATLAS’s water is rich in deuterium based on coordinated observations with ALMA and the MDM Observatory.
- The team measured a deuterium-to-hydrogen ratio about 30 times higher than in comets from our solar system and about 40 times higher than in Earth’s oceans.
- The isotopic ratio points to formation at temperatures below roughly 30 kelvin in a low-radiation region such as a prestellar cloud or the far reaches of a protoplanetary disk.
- 3I/ATLAS is only the third known interstellar visitor and showed intense activity, with ESA estimating daily water loss equal to about 70 Olympic swimming pools.
- The findings show planetary systems can form under very different conditions and highlight the value of rapid, high-sensitivity follow-up while reinforcing calls to protect dark skies for future discoveries.