Astronomers have achieved a groundbreaking feat by detecting phosphine on Venus, a biosignature that suggests the possibility of life.
Speaking at the Royal Astronomical Society's National Astronomy Meeting 2023 in Cardiff this week, Jane Greaves of Cardiff University in Wales unveiled the discovery of phosphine at deeper atmospheric levels of Venus than previously observed.
"There's a prominent theory suggesting that phosphine could form by releasing phosphorus-bearing rocks into the upper atmosphere, where they react with water and acids to produce phosphine gas," Greaves explained.
Phosphine, a Biosignature
Phosphine is a colourless, flammable gas at room temperature with a pungent odour resembling garlic or decaying fish. Exposure to phosphine can cause nausea, vomiting, stomach pain, diarrhoea, thirst, muscle pain, difficulty breathing, and pulmonary oedema. Higher and prolonged exposures can lead to serious health risks.
Occurrence
Phosphine exists in trace amounts in Earth's atmosphere and plays a role in the global phosphorus biochemical cycle. It is likely produced through the reduction of phosphate in decomposing organic matter, possibly via partial reductions and disproportionations. Natural environmental systems typically lack strong reducing agents capable of directly converting phosphate to phosphine.
Toxicity and Safety
Phosphine primarily acts as a redox toxin, damaging cells by inducing oxidative stress and impairing mitochondrial function.
Uses
Industrially, phosphine is utilised for pest control in stored grain and tobacco, effectively eliminating insects and rodents.