GLOW: Following the Phosphorus: Constraining the Location of Habitable Worlds through an Astronomical and Petrological Lens

The search for habitable worlds in the Universe is one of the highest priorities within Astronomy and Earth and Planetary sciences; yet a pathway to answering whether there is life in our Galaxy and beyond has not yet emerged. This project aims to chart a path towards determining where life may (or may not) exist using a novel interdisciplinary framework.

More specifically, the goal is to combine Astronomy and Petrology to constrain the location of potentially habitable worlds using observational and experimental techniques to understand how the key elements for life, specifically Phosphorus, are distributed across the Galaxy and beyond, and what the required amount of these key elements are for life to exist. This work will focus on Phosphorus, in part, because it is a primary nutrient limiting the biological productivity at the planet surface over geologic timescales.

The search for life is not only a crucial scientific exploration, but it also has the ability to inspire broader impacts. The broader impacts of this work center on engaging, empowering, and recruiting young future scientists with diverse backgrounds at various levels.

This project responds to the Dear Colleague Letter NSF 22-032: Geoscience Lessons for and from Other Worlds (GLOW) by charting an interdisciplinary pathway to constraining where in the universe life could exist. The proposed activities “considers the Earth in the context of planetary bodies” by developing a novel framework based on Phosphorus to broaden understanding of habitable worlds in the Galaxy and beyond.

More specifically, this project aims to fill the knowledge gaps of Phosphorus regarding its cosmic distribution and behaviors inside of planetary bodies. This will be accomplished by: (1) measuring phosphorus abundances in stars in two distinct regions of the Universe (i.e., the Milky Way and the Gaia Enceladus dwarf galaxy) through astronomical observations and (2) building new predictive models for phosphorus partitioning in metal-silicate and mineral-melt systems.

The first part of the project will constrain how much bulk phosphorus can exist in a cosmic environment, while the second part will determine, given the bulk phosphorus available, whether the phosphorus can be found on a planetary surface as needed by life. The key outcomes of this project will be the establishment of a new framework linking the compositions of planet hosting stars to phosphorous abundances at rocky planet surfaces required to determine if life could exist.

This framework can combine astronomical and petrological studies to constrain the locations of habitable worlds in the Galaxy and beyond.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.