An artistic illustration showing comets delivering both regular and heavy water to Earth. Image credit: NSF/AUI/NSF NRAO/P. Vosteen, B. Saxton
At Fact Fun, we often look back at Earth’s origins, but this time scientists looked even further — and what they found rewrites our cosmic story. According to new research, the water flowing in our oceans might be billions of years older than the Sun itself.
🔭 A Telescope Peering Back In Time
Using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, astronomers studied a young star called V883 Orionis, located in the Orion constellation about 1,305 light-years from Earth. Its surrounding disk of gas and dust is where planets are forming — a cosmic snapshot of how our Solar System began 4.6 billion years ago.
Within this disk, researchers detected heavy water (D₂O) — a form of H₂O that contains deuterium, a heavier isotope of hydrogen. The ratio of heavy water to normal water was virtually identical to that found in comets within our Solar System, suggesting that Earth’s oceans and space-born ice share the same ancient origin.
💧 Older Than Our Star
Lead author John Tobin of the National Radio Astronomy Observatory (NRAO) explained that this discovery links the chemical signature of our planet’s water to interstellar molecular clouds that existed before the Sun formed.
“The water we drink today may be billions of years older than our Sun,” Tobin said.
The research, published in Nature (2024), suggests that much of the water present in our Solar System — including that on Earth — did not originate here but was inherited from the cold molecular cloud that collapsed to form our star and planets.
🧩 How Heavy Water Tells Ancient Stories
Because deuterium forms only in extremely cold conditions (around –250 °C), the presence of heavy water is like a chemical fossil marking where and when it was born. By tracing these ratios in V883 Orionis’s disk, astronomers can follow the journey of water from interstellar space to newborn worlds — showing that the same molecules once floated in space long before Earth took shape.
💡 Did You Know?
Water is a time traveler. Some of the molecules inside you may have been drifting through space since before our Solar System existed.
If cosmic origins fascinate you, explore the mystery of the Universe’s rotation and the Hubble tension or how NASA detected a 7,000-kilometer gravity anomaly over the Atlantic — two other stories that push our understanding of space even further.
ref : IFLScience , Nature
