Hydrogen made up nearly all of the matter in the universe following the Big Bang. Later, further elements were created through nuclear processes occurring within stars or during star explosions known as novae or supernovae. However, stars differ in many ways, as do the methods by which they can explode. The mechanisms that contributed to the abundance of elements observed in the universe are still being studied by astronomers.
Astronomers have proposed a novel theory to explain the genesis of phosphorus, an element essential to life on Earth. The theory points to a star explosion called “ONe nova” as a significant phosphorus source.
Astronomers proposed a new model based on oxygen-neon novae, denoted as “ONe novae,” to explain the abundance of phosphorus.
When material accumulates on the surface of a white dwarf star rich in oxygen, nitrogen, and magnesium and heats up to the point where explosive runaway nuclear fusion occurs, the result is a supernova.
According to this model, a nova will release a substantial amount of phosphorus, and the frequency of novae will be influenced by the star’s chemical makeup, particularly their iron content. This suggests that phosphorus, a key element for life, would have been readily available when the solar system first began to form, some 4.6 billion years ago, coinciding with the estimated peak of ONe nova about 8 billion years ago.
According to the model, ONe novae will provide a chlorine enhancement comparable to the phosphorus enhancement. This is a testable hypothesis to verify the viability of the ONe novae model; however, there is not yet enough observational data for chlorine to support it.
Future observations of stars in the outermost region of the Milky Way galaxy will provide crucial data needed to validate the anticipated iron reliance and chlorine enhancement and determine whether a revision of the ONe novae model is necessary. These observations are of paramount importance to the advancement of our understanding of phosphorus and the universe.
Journal Reference:
- Kenji Bekki et al., Phosphorus Enrichment by ONe Novae in the Galaxy, The Astrophysical Journal Letters (2024). DOI: 10.3847/2041-8213/ad3fb6
