Did you know that there is a cosmological lithium problem? I did not, but a team led by scientists at the University of North Carolina at Chapel Hill did, and they may have taken the first steps to solve this problem in new work published in the journal Science.

We use lithium for a host of important purposes, from powering cell phones to creating medicine. And we are pretty certain that much of the lithium in our universe was created during the Big Bang. But we haven’t been able to measure that lithium anywhere in the stars, and that is the problem.

Enter this team of researchers, who took spectra of two very old white dwarfs and found the crushed up remains of what were likely large asteroids. From the spectra, the team was able to determine the composition of those former rocky bodies, and they managed to measure both lithium and potassium for the first time.

J. Christopher Clemens, the designer of this new spectrograph, explained the importance of the discovery: Our measurement of lithium from a rocky body in another solar system lays the foundation for a more reliable method of tracking the amount of lithium in our galaxy over time

And lead author Ben Kaiser noted: Eventually with enough of these white dwarfs that had asteroids fall on them, we will be able to test the prediction of the amount of lithium formed in the Big Bang.

It’s always a good day in science when we have a breakthrough on a long-standing problem, so hats off to this team and their amazing work.

More Information

Eureka Alert article 

“Lithium pollution of a white dwarf records the accretion of an extrasolar planetesimal,” B. C. Kaiser et al., 2020 December 17, Science