Dwindling phosphorus supply could mean fewer aliens
Phosphorus, while probably not part of your daily lexicon, is one of just six chemical elements on which Earthly life depends. The element, represented by the chemical code ‘P’, is also a key component of adenosine triphosphate (ATP), the compound which cells use to store and transfer energy. Not one of your more expendable elements, then, phosphorus.
But work conducted by the astronomy team at Cardiff University has found that cosmic supplies of phosphorus may be harder to come by than previously thought. It’s only recently that astronomers have started paying attention to the cosmic origins of the stuff, explains leader of the study Dr Jane Greaves to Phys.org. The results have been surprising, she continues: “In particular, P is created in supernovae – the explosions of massive stars – but the amounts seen so far don’t match our computer models. I wondered what the implications were for life on other planets if unpredictable amounts of P are spat out into space and later used in the construction of new planets.”
The team’s research was conducted using the William Herschel Telescope on the Canary Islands to study the Crab Nebula, the remnant of a supernova that’s 6500-odd light years away near the constellation of Taurus. Observation was conducted on infrared light from phosphorus and iron, and what’s been deduced thus far is that there is far less phosphorus emanating from the Crab Nebula than predicted.
Indeed, the only previous study (of this magnitude) to be conducted on phosphorus examined the Cassiopeia A (Cas A) supernova remnant, whose phosphorus levels far exceeded that of the Crab Nebula. The discrepancy, astronomers posit, derives from the fact that the former remnant was borne of the explosion of a supermassive star.
What makes this important? Well, given that phosphorus is involved in the creation of proto-biomolecules, it’s responsible for life. If the vital chemical element is borne of supernovae, and travels across space in meteoritic rocks, it’s very much a game of luck as to whether young planets are bestowed with any of the critical element. Earth itself is thought to be the lucky recipient of just a few measly phosphorus-bearing meteorites. What hope then for other nascent planets, potential breeding grounds for extraterrestrial life? If phosphorus is dwindling as much as this study suggests, “life might really struggle to get started out of phosphorus-poor chemistry, on another world otherwise similar to our own,” explains co-leader Dr. Phil Cigan.
Nothing’s conclusive yet, as a series of foggy nights frustrated the experiment back in November of last year, meaning astronomers are just beginning to glean scientific results. But findings have spurred on further action; “We’ve just asked for more telescope time to go back and check,” explains Dr. Cigan, “in case we’ve missed some phosphorus-rich regions in the Crab Nebula”. Here’s hoping: life really does depend on it.