Phosphorus, an essential component of life as we know it, was thought to be relatively rare in space. But now astronomers have discovered a surprising amount of matter on the outskirts of the galaxy; This suggests that life may be more common in space.

Life on Earth requires the six most essential elements: nitrogen, carbon, hydrogen, oxygen, phosphorus and sulfur (NCHOPS). Most of them are relatively easy to find because ordinary low-mass stars escape into space when they reach the end of their lives. Phosphorus, meanwhile, is much rarer and is therefore generally considered a limiting factor for life in the universe.

“It takes a violent event to make phosphorus,” said the study’s corresponding author, Lucy Ziuris. — Phosphorus is believed to be formed during a supernova explosion, which required a star at least 20 times the mass of the Sun. “In other words, if you want life, you better be close to a supernova, if that’s really the only source from which phosphorus is made.”

But in a new study, astronomers found phosphorus where it “shouldn’t be”; This points to unknown mechanisms for the formation of phosphorus; Phosphorus may turn out to be more abundant than we thought. The team used radio telescopes at the Arizona Radio Observatory and IRAM in Spain to observe the molecular cloud called WB89-621. And indeed they found characteristic signs of phosphorus monoxide and phosphorus nitride.

This cloud is located about 74,000 light-years from the center of the Milky Way, almost twice as far away as the previously found phosphorus. There isn’t enough matter there, in the outskirts of the galaxy, to form massive stars that produce phosphorus after death.

So how did it get there? Previously proposed mechanisms include “galactic fountains” that direct it from the center and spray it across the disk. But little evidence has been found to support this story, and even if there were, the sources are not expected to reach much further. Instead, the team suggests that low- and medium-mass stars could produce phosphorus by removing neutrons from carbon atoms. adding them to atoms.silicon

“This has been suggested in theory, and so it could explain another source of phosphorus in addition to the supernova, and I think we now have strong evidence to support that,” Zuris said. said.

Other groups have also found evidence of phosphorus-rich stars that may contribute. This astrochemical discovery could have important implications for extraterrestrial life. The relative rarity of phosphorus is thought to place a strict limit on how common life is in the universe. But if it can be found everywhere in our galaxy, we may have prematurely eliminated promising planets.

“For a planet as we know it to be habitable, you have to have all the NCHOPS elements, and their presence defines the galactic habitable zone,” Ziuris said. said. “Thanks to the discovery of phosphorus, they have now all been found at the edge of the galaxy, extending the habitable zone to the galactic outskirts.” Source