We often think of gold as a precious metal that we find here on Earth, but its journey might actually start from a massive cosmic explosion. For a long time, scientists believed that the rare collisions between neutron stars were the only known way gold and other heavy elements were created in the universe. But now, after reanalyzing old space data, there’s a new twist to the story: magnetars– a special kind of neutron star– could also be involved in creating these heavy elements. This discovery gives us a new perspective on one of astronomy's biggest questions: how did some of the heaviest materials in the universe, like gold, come to be?
Most of the lighter elements, like hydrogen, helium, and some lithium, were formed soon after the Big Bang. Heavier elements like iron came later, created in supernova explosions. But when it comes to gold, which is heavier than iron, its origin has remained one of the biggest mysteries in astrophysics.
“It’s a pretty fundamental question in terms of the origin of complex matter in the universe,” said Anirudh Patel, lead author of the study and a doctoral researcher in physics at Columbia University. “It’s a fun puzzle that hasn’t actually been solved.”
Until now, the only confirmed way gold is created in space was through the collision of two neutron stars. According to the report, these events, called kilonovas, produce strong gravitational waves, bright bursts of radiation, and heavy elements like gold and platinum. A well-known example of this was seen in 2017, which became a key moment in our understanding of cosmic chemistry.
However, there’s a timing issue. “It is believed that most neutron star mergers occurred only in the past several billion years,” explained study co-author Eric Burns, an astrophysicist at Louisiana State University. That raises the question: how did heavy elements appear so early in the universe’s history?
To dig deeper into this, researchers turned to data from a powerful magnetar flare that was spotted in December 2004 by the INTEGRAL space mission. At the time, the gamma-ray signal was recorded, but no one really knew what it meant. When the team compared this flare with predictions from earlier models, especially those by Brian Metzger, a professor at Columbia University, the findings were eye-opening.
“When initially building our model and making our predictions back in December 2024, none of us knew the signal was already in the data. And none of us could have imagined that our theoretical models would fit the data so well. It was quite an exciting holiday season for all of us,” Patel shared.
NASA’s RHESSI and Wind satellites also picked up supporting signals, adding even more credibility to the discovery.
Magnetars are a special kind of neutron star. They have incredibly strong magnetic fields and are known for releasing bright, short-lived flares. Scientists believe these bursts are caused by what they call “starquakes.”
“Neutron stars have a crust and a superfluid core,” said Burns, as quoted by CNN. “The motion under the surface builds up stress on the surface, which can eventually cause a starquake. On magnetars, these starquakes produce very short bursts of X-rays. Just like on Earth, you (have) periods where a given star is particularly active, producing hundreds or thousands of flares in a few weeks. And similarly, every once in a while, a particularly powerful quake occurs.”
The team believes that these powerful flares could send material from the star’s crust flying into space, and under the right conditions, this could lead to the creation of heavy elements.
“They hypothesized that the physical conditions of this explosive mass ejection were promising for the production of heavy elements,” Patel said.
While the evidence is strong, experts not involved in the study have warned that the findings should be considered a possibility, not a definite conclusion. According to the report, Dr. Eleonora Troja, an astrophysicist at the University of Rome who led the team that discovered X-rays from the 2017 neutron star collision, said: “The production of gold from this magnetar is a possible explanation for its gamma-ray glow, one among many others as the paper honestly discusses at its end.”
She also noted the unpredictable nature of magnetars. “Magnetars are very messy objects,” she said, as quoted by CNN. Because the formation of heavy elements requires very specific conditions, there’s a chance that magnetars could end up creating lighter elements like zirconium or silver instead.
“Therefore, I wouldn’t go so far as to say that a new source of gold has been discovered,” she added. “Rather, what’s been proposed is an alternative pathway for its production.”
The researchers believe that huge magnetar flares could account for up to 10% of the heavy elements in our galaxy. However, more observations are needed to fully understand their role. NASA’s upcoming Compton Spectrometer and Imager (COSI) mission, set to launch in 2027, could provide clearer answers. It will be able to observe gamma rays from these flares, helping to confirm if magnetars can actually produce gold and similar elements.
As Patel reflected on the larger implications, he said, “It's very cool to think about how some of the stuff in my phone or my laptop was forged in this extreme explosion (over) the course of our galaxy’s history.”
The study was published in The Astrophysical Journal Letters.