Origin of Water in the Universe: Population III Supernovae
Why in the news
A new study offers an answer to how water first appeared in the cosmos, pointing to the violent deaths of the very first stars.
Key facts
- The Big Bang occurred about 13.8 billion years ago; the first stars formed a few hundred million years later from only hydrogen and helium.
- These massive stars used up their hydrogen and exploded as supernovae.
- The supernovae released oxygen, which combined with hydrogen to form water.
- Team led by D.H. Whalen (University of Portsmouth) used advanced 3D simulations.
Star populations
| Type | Description |
|---|---|
| Population I | Youngest, metal-rich, like the Sun |
| Population II | Older, lower metallicity |
| Population III | First generation; massive, purely hydrogen and helium; possible first water makers |
Significance
- Early supernovae made more water than believed, so water-bearing planets may have formed far earlier.
- The timeline for possible life could shift back by billions of years.
Limitations
- Population III stars are too far to observe, so results rest on simulations.
- Whalen says the models capture ionising UV radiation and gas dynamics using established stellar evolution theory.
Exam angle
- Journal: Nature Astronomy; stars: Population III.