Scientists have found new, peculiar stars that could help shed light on how life could begin in the universe.
Phosphorus is key for understanding the story of our universe, and of life on Earth. It forms a part of the DNA and RNA molecules that together create more complex structures including humans, and is required to power cells and their membranes.
But it also remains largely mysterious. Theoretical models of the evolution of chemicals within the galaxy have not been able to explain either the origin or the quantity of phosphorus that can be found within the Milky Way and our solar system.
Our current account of the way those chemicals come about suggests there should be far less phosphorus than is actually found. Measurements show that it is relatively abundant, enough to create life and contribute to other key processes.
The new study attempted to solve that problem by looking at different stars in an attempt to better understand those processes. To do so, researchers looked at the infrared light coming from different stars in the Sloan Digital Sky Survey, a public database of space objects.
But in those stars they found a peculiar and unexpected chemistry. They were rich in phosphorus, but also other elements, such as magnesium and oxygen. After deep analysis, detailed in a paper newly published in Nature, the researchers found that such a chemical pattern could not be explained by our current understanding of the evolution of stars.
Scientists found 15 of the stars with “unusual” amounts of a variety of elements. They noted that they probably inherit their strange chemistry from another stellar source, but that their “intriguing” makeup is a challenge to existing theories.
Instead, new effects in those massive stars are needed as alternative explanations for why such phosphorus-rich stars exist and can be seen in the universe.
“These results show that not only are we dealing with a new type of objects, but that their discovery opens the way for the exploration of new physical mechanisms and nuclear reactions which occur in stellar interiors,” said Instituto de Astrofísica de Canarias researcher Thomas Masseron, the leader of the project and the first author of the article, in a statement.
Astronomers now hope a better understanding of those objects could also help give us a clue as to the understanding of phosphorus, and its role as a fundamental component of life.
Related stars could be the origin of the phosphorus that now surrounds us on Earth today, the authors write in an article titled ‘Phosphorus-rich stars with unusual abundances are challenging theoretical predictions’ and published in Nature Communications.