We finally know where gold came from in the universe
What's the story
The answer to one of astrophysics' greatest mysteries—the origin and distribution of elements heavier than iron in the universe (like gold)—have been revealed in a recent study.
Led by Anirudh Patel, a doctoral student at Columbia University, the study suggests that heavy elements may have been produced by flares from highly magnetized neutron stars known as magnetars.
The findings are detailed in The Astrophysical Journal Letters.
Stellar phenomena
Magnetars: The cosmic powerhouses
Magnetars are a rare breed of neutron stars, known for their incredibly powerful magnetic fields.
They are the remnants of supernova explosions and are so dense that a single teaspoon of their material would weigh a billion tons on Earth.
Sometimes, magnetars emit large doses of high-energy radiation during "starquakes," which break the neutron star's crust and can even affect Earth's atmosphere.
Explosions
Magnetar flares could account for 10% of heavy elements
Patel's study estimates that the giant flares from magnetars might contribute up to 10% of the total abundance of elements heavier than iron in our galaxy.
This means gold, one of these heavy elements, may have been formed this way during the early history of the universe.
The research also indicates magnetar flares can heat and eject neutron star crustal material at high speeds, making them a potential source for heavy element creation.
Process
How do magnetars create heavy elements?
The creation of heavy elements in a magnetar occurs through high-energy radiation from giant flares.
This radiation can make neutrons forge lighter atomic nuclei into heavier ones, forming new elements.
In an environment like that of a disrupted neutron star, single atoms can quickly capture so many neutrons that they undergo multiple decays, creating much heavier elements like uranium.
Data analysis
Old data reveals new insights about heavy elements
The research team initially expected signs of heavy element creation and distribution in a magnetar to appear in visible and ultraviolet light. However, co-author Eric Burns proposed checking for a gamma-ray signal.
On reviewing data from the last giant flare observed in December 2004, they found a smaller signal from the magnetar closely matching their predictions.
This gamma-ray signal corresponded to what it should look like when heavy elements are created and distributed in a magnetar giant flare.
Next steps
Future research and implications
NASA's upcoming Compton Spectrometer and Imager (COSI) mission is expected to delve deeper into these findings.
Launching in 2027, COSI will examine energetic phenomena in the cosmos, like magnetar giant flares.
The telescope will identify individual elements created in these events, offering new insights into the origin of elements.
Patel expressed his excitement about this research, saying, "It's very cool to think about how some of the stuff in my phone or my laptop was forged in this extreme explosion."