A recent study led by researchers from Louisiana State University and Columbia University revealed that gigantic explosions from magnetars could be responsible for creating up to 10% of the elements heavier than iron in the Milky Way galaxy, including gold. Magnetars are extremely dense remnants of exploded stars, possessing incredibly powerful magnetic fields and capable of releasing enormous amounts of energy in the form of gamma-ray flares.
"This is a quite fundamental question in terms of the origin of complex matter in the universe. This is actually an unsolved fun puzzle," said Anirudh Patel, the lead author of the study and a PhD student at Columbia University, according to CNN.
The study analyzed archival data from NASA and European Space Agency telescopes collected two decades ago. Researchers found evidence suggesting that magnetars can emit intense bursts of radiation known as "starquakes," which eject materials rich in heavy elements like gold into space at extremely high speeds.
During starquakes, internal pressure causes the crust of magnetars to be torn apart, and the matter inside, especially just below the crust, can be heated instantly to billions of degrees, releasing a large amount of neutrons. These conditions create a favorable environment for forming heavy elements.
The December 2004 burst from the magnetar SGR 1806-20 released energy equivalent to hundreds of thousands of years of the Sun's emission and was one of the strongest gamma-ray bursts ever recorded. The gamma-ray signals recorded two decades ago correspond to the scenario of heavy element formation from magnetar bursts, supporting the team's proposal about the creation and distribution of heavy elements in a giant magnetar flare.
"It's very fun to think that some parts of my phone or laptop might have formed from extreme explosions throughout the history of our galaxy," Patel said.
Previously, long-standing hypotheses suggested that supernova explosions or neutron star collisions were the main sources of gold and other heavy elements in the universe. In 2017, astronomers observed the collision of two neutron stars, which led to gravitational waves and a gamma-ray burst, creating heavy elements like gold, platinum, and lead, further supporting the role of neutron star collisions in cosmic element production.
However, researchers now point out that there may be an even more powerful source of gold production from a rare and strange celestial object: magnetars, which may drive ancient processes of gold production and release materials rich in heavy elements during starquakes.
"We believe that most neutron star mergers only occurred in the last few billion years," said Eric Burns, co-author of the study and professor of astrophysics at Louisiana State University, according to CNN.
Understanding how these elements formed in the early cosmos is crucial for astrophysics and cosmology. The study's conclusions emphasize the importance of magnetars in the chemical history of the cosmos, particularly in the formation of heavy elements through rapid neutron capture.
Researchers found evidence suggesting that a magnetar ejects material during a giant flare, but they do not have a physical explanation for the star's mass ejection, Patel said.
"But a future mission could provide a more accurate estimate," Patel added.
The upcoming COSI gamma-ray telescope, scheduled for launch in 2027, is designed to observe giant magnetar flares and identify the elements created in them, potentially providing accurate data about magnetic flares and their elemental composition. COSI will study energetic phenomena in the cosmos, including the giant flares of magnetars, and will observe in the so-called soft gamma radiation.
"This answers one of the big questions of this century and solves a mystery using almost forgotten archival data," Burns said.
The article was written with the assistance of a news analysis system.