Since the Big Bang, the early universe has contained hydrogen, helium, and a minimal amount of lithium. Heavier elements, such as iron, were formed within stars. Yet, one of astrophysics’ greatest enigmas is how the first elements heavier than iron, like gold, were created and dispersed throughout the cosmos. A recent study by astronomers at Columbia University and other institutions suggests that a single flare from a magnetar could generate 27 equivalent masses of these elements simultaneously.
Impressions of Magnetar artists. Image credit: NASA’s Goddard Space Flight Center/S. Wesinger.
For decades, astronomers have theorized about the origins of some of nature’s heaviest elements, like gold, uranium, and platinum.
However, a fresh examination of older archival data indicates that up to 10% of these heavy elements in the Milky Way may originate from the emissions of highly magnetized neutron stars, known as magnetars.
“Until recently, astronomers largely overlooked the role that magnetars, the remnants of supernovae, might play in the formation of early galaxies,” remarked Todd Thompson, a professor at Ohio State University.
“Neutron stars are incredibly unique, dense objects known for their large size and strong magnetic fields. They are similar to black holes but not quite the same.”
The origin of heavy elements has long been a mystery, but scientists have understood that these elements can only form under specific conditions through a process known as the R process (or rapid neutron capture process).
This process was observed in 2017 when astronomers detected a collision between two super-dense neutron stars.
This event was captured using NASA telescopes and the LIGO gravitational wave observatory, providing the first direct evidence that heavy metals can be produced by celestial phenomena.
However, subsequent evidence suggests that neutron star collisions may not form heavy elements swiftly in the early universe, indicating that additional mechanisms might be necessary to account for all these elements.
Based on these insights, Professor Thompson and his colleagues realized that powerful magnetar flares could act as significant ejectors of heavy elements. This conclusion was validated by the observation of the SGR 1806-20 magnetar flare that occurred 20 years ago.
By analyzing this flare event, the researchers found that the radioactive decay of the newly formed elements aligns with theoretical predictions concerning the timing and energy released by magnetar flares after ejecting heavy R-process elements.
“This is the second time we’ve observed direct evidence of where these elements are produced, first linked to neutron star mergers,” stated Professor Brian Metzger from Columbia University.
“This marks a significant advancement in our understanding of heavy element production.”
“We are based at Columbia University,” mentioned Anildo Patel, a doctoral candidate at the institution.
The researchers also theorized that magnetar flares generate heavy cosmic rays and very fast particles, the origins of which remain unclear.
“I am always excited by new ideas about how systems and discoveries in space operate,” said Professor Thompson.
“That’s why seeing results like this is so thrilling.”
The team’s paper was published in The Astrophysical Journal Letters.
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Anirudh Patel et al. 2025. Direct evidence for R-process nuclear synthesis in delayed MeV radiation from SGR 1806-20 magnetar giant flares. ApJL 984, L29; doi: 10.3847/2041-8213/ADC9B0
Source: www.sci.news
