Astronomers have used the Submillimeter Telescope of the Arizona Radio Observatory to identify phosphorus in the form of PO and PN in oxygen-rich circumstellar envelopes. A recent study examines these cases and reports peak abundances for PO and PN around asymptotic giant branch (AGB) stars and supergiants. The findings provide insight into the processes that may have led to the abundance of PO and PN in these systems. The results also suggest that phosphorus-bearing molecules are common in oxygen-rich envelopes, and that a significant amount of P could remain in the gas phase.

The study, “New Circumstellar Sources of PO and PN: The Increasing Role of Phosphorus Chemistry in Oxygen-rich Stars,” was published in The Astrophysical Journal. The work was supported by the Nexus for Exoplanet System Science (NExSS). NExSS is a NASA research coordination network supported in part by the NASA Astrobiology Program. This program element is shared between NASA’s Planetary Science Division (PSD) and the Astrophysics Division.