Crucial Ingredient of Life Might Not Exist Across Universe, Scientists Discover

If you were going grocery shopping with plans to whip up life, you'd know to stock up on the equivalent of a chocolate chip cookie recipe's eggs and chocolate chips: It's easy to remember you need water and carbon. But just as you may forget to check your supply of baking soda, the less obvious ingredients of life—like phosphorus—may slip your mind.

Phosphorus is a crucial piece of DNA and the compounds that store energy. A cookie without baking soda doesn't quite taste right, but life as we know it without phosphorus simply stops. That's why Jane Greaves, an astronomer at Cardiff University, was surprised to see that not many astronomers have looked at how the element is distributed across the universe—there was just one paper that fit the mark.

So she decided to look herself, arranging time on a telescope based in the Canary Islands to study two supernova remnants. Those remnants are the rubble left over from the explosions of dying stars, which in turn become incorporated into newly forming planets.

According to the project's preliminary findings, which Greaves and a colleague are presenting at a conference being held this week in the U.K., the two remnants show markedly different levels of phosphorus. That suggests the element isn't distributed very evenly across the universe, which could throttle life elsewhere.

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"I think people didn't really think about [phosphorus]" in comparison to ingredients like carbon and water, Greaves told Newsweek. "It's kind of a nice opportunity to go, 'Look, this matters and it's not super hard.'"

Usually, Greaves spends her time studying the clouds of dust and gas that form around young stars and eventually clump together into planets. For this project, she learned an observing technique that analyzes the different colors of light produced by the supernova remnants. Scientists can use that information to decipher which elements are present.

"Now we've shown you can actually do this, we can try a few more supernova remnants," Graves said.

Having only limited amounts of phosphorus available may not be a total dealbreaker for life, even life as we know it, according to Avi Loeb, an astronomer at Harvard University in Massachusetts who wasn't involved with the new research.

"It's still possible that there would be pockets," Loeb said of phosphorus and other elements that are necessary for life but tend to go unrecognized. (Another such element, he adds, is molybdenum, which living things need in order to pull nitrogen out of the environment and into usable formats.)

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The remnants of the Cassiopeia A supernova, where Greaves and her colleagues found higher levels of phosphorus. NASA/JPL-Caltech/L. Rudnick (University of Minnesota)

But the spottiness of element distributions may mean we should think more creatively about what types of life we look for beyond our planet. "The conditions that we take for granted here on Earth in terms of the abundance of elements are not necessarily universal," Loeb said. "It's just an interesting point that has not been discussed much in the literature."

Greaves says that simply identifying phosphorus on its own isn't enough, since life can't use it until it's incorporated into a mineral. "You don't really have a way to get it into biology," Greaves said. She's hoping to work with meteorite experts to try to track what sorts of phosphorus compounds these space rocks carry in order to try to bridge that gap.

After all, it's not quite enough to just buy the baking soda—you also have to remember to put it in the bowl before it can transform your cookie dough.