A recent study carried out by Ohio State University proposes that magnetar flares, immense explosions in space, could be a direct source for the creation and spread of heavy elements throughout the universe. The study was recently published in The Astrophysical Journal Letters.
Image Credit: Jurik Peter
For many years, astronomers have only had theoretical explanations for the origin of some of the heaviest elements found in nature, such as gold, uranium, and platinum. However, by re-examining existing archival data, researchers now estimate that as much as 10% of these heavy elements within the Milky Way galaxy originate from the material ejected by highly magnetized neutron stars known as magnetars.
“Neutron stars are very exotic, very dense objects that are famous for having really big, very strong magnetic fields. They’re close to being black holes, but are not,” said Thompson.
The origins of heavy elements had puzzled scientists for a long time. They knew these elements could only form under very specific conditions, through a complex sequence of nuclear reactions known as the r-process, or rapid neutron capture, according to Thompson.
Scientists directly observed this process in action during the 2017 collision of two incredibly dense neutron stars. This event, captured by NASA telescopes, the Laser Interferometer Gravitational-wave Observatory (LIGO), and other instruments, provided the first concrete evidence that heavy metals were indeed created by powerful cosmic events.
However, subsequent evidence suggested that other mechanisms might be necessary to account for the abundance of these elements, as neutron star collisions might not have produced heavy elements quickly enough in the early universe. This new study, building upon these clues, led Thompson and collaborators to realize that intense magnetar flares could indeed serve as potential sources for ejecting heavy elements.
The study was supported by two-decade-old observations of SGR 1806–20, a magnetar flare so exceptionally bright that some of its measurements could only be obtained by studying its reflection off the Moon.
By analyzing this magnetar flare event, researchers determined that the radioactive decay of the newly formed elements aligned with their theoretical predictions regarding the timing and types of energy released by a magnetar flare after it expelled heavy r-process elements. The researchers also proposed that magnetar flares generate high-energy cosmic rays, extremely fast-moving particles whose physical origin remains unknown.
I love new ideas about how systems work, how new discoveries work, how the universe works. That’s why results like this are really exciting.
Todd Thompson, Study Co-Author and Professor, Astronomy, The Ohio State University
Magnetars could offer unique perspectives on how chemical elements evolve within galaxies, including the formation of planets outside our solar system (exoplanetary systems) and their potential to support life (habitability).
Beyond producing precious metals like gold and silver that eventually find their way to Earth, the supernova explosions that give rise to magnetars also create elements such as oxygen, carbon, and iron, which are crucial for numerous other, more intricate cosmic processes.
All of that material they eject gets mixed into the next generation of planets and stars. Billions of years later, those atoms are incorporated into what could potentially amount to life.
Todd Thompson, Study Co-Author and Professor, Astronomy, The Ohio State University
These discoveries have profound implications for astrophysics, especially for scientists investigating the origins of both heavy elements and fast radio bursts – fleeting bursts of electromagnetic radio waves originating from distant galaxies. Gaining insight into how matter is expelled from magnetars could enhance the understanding of these enigmatic objects.
Due to their infrequent occurrence and short lifespan, magnetar flares are challenging to observe. Current space-based telescopes, such as the James Webb Space Telescope and Hubble, lack the specific capabilities required to detect and study their emission signals. Even more specialized observatories like NASA’s Fermi Gamma-ray Space Telescope can only detect the brightest gamma-ray bursts from nearby galaxies.
However, a proposed NASA mission, the Compton Spectrometer and Imager (COSI), could significantly support the team’s research by surveying the Milky Way for energetic events like giant magnetar flares. While another event comparable to SGR 1806-20 might not happen this century, if a magnetar flare were to occur in the galactic neighborhood, COSI could be used to better identify the specific elements created by its eruption, potentially allowing this team of researchers to confirm their theory about the cosmic origins of heavy elements.
“We’re generating a bunch of new ideas about this field, and ongoing observations will lead to even more great connections,” said Thompson.
Funding for this study was provided by the National Science Foundation, NASA, the Charles University Grant Agency, and the Simons Foundation. Co-authors on the research include Anirudh Patel and Brian D. Metzger from Columbia University, Jakub Cehula from Charles University in Prague, Eric Burns from Louisiana State University, and Jared A. Goldberg from the Flatiron Institute.
Journal Reference:
Patel, A., et al. (2025) Direct Evidence for r-process Nucleosynthesis in Delayed MeV Emission from the SGR 1806–20 Magnetar Giant Flare. The Astrophysical Journal Letters. doi.org/10.3847/2041-8213/adc9b0