Gold born in supernovae and neutron star collisions
The place does gold come from? It comes from the ground, in fact, however Earth’s gold originated in outer space. It’s produced in supernovae (exploding stars), and in neutron star collisions, in a set of nuclear reactions identified to scientists because the r-process. Astronomers utilizing state-of-the-art telescopes have found a whole bunch of gold-rich stars in our Milky Way galaxy. However they’ve wished to know when, the place, and the way these stars shaped. On November 14, 2022, the Royal Astronomical Society – based mostly in London – introduced a brand new numerical simulation, displaying that almost all gold-rich stars have been shaped in low-mass dwarf galaxies that merged with our Milky Way some 10 billion years in the past.
They stated this new work sheds mild on these stars’ previous for the primary time. And so they identified that gold-rich stars compose a “fossil file,” thus giving astronomers a brand new instrument to make use of in probing our galaxy’s historical past.
The scientists conducting the examine are from the College of Notre Dame and Tohoku College. The analysis appears within the peer-reviewed scientific journal Month-to-month Notices of the Royal Astronomical Society.
Tracing Milky Way historical past
These astronomers are utilizing the time period “gold-rich” to explain stars that comprise excessive abundances of heavy components (these heavier than iron), together with what they known as “jewellery retailer components,” gold and platinum.
They used the ATERUI II supercomputer within the Centre for Computational Science on the Nationwide Astronomical Observatory of Japan to provide their numerical simulation. They stated it tracks the Milky Way’s formation from the Huge Bang to the current, with a excessive stage of element with respect to time. They stated:
This simulation has the very best time resolution but achieved: it could actually exactly resolve the cycle of supplies shaped by stars within the Milky Way …
The usual cosmology it used predicts that the Milky Way grows by the accretion and merging of small progenitor galaxies [the small galaxies that merged with our Milky Way to create the large galaxy we live in today].
Gold-rich stars as ‘fossils’
The simulation information revealed that a few of the progenitor galaxies – people who existed over 10 billion years in the past – contained giant quantities of the heaviest components. These heavy components got here from neutron star mergers, they stated, a identified supply of heavy component creation. They stated:
The gold-rich stars shaped in these galaxies, and their predicted abundances will be in contrast with the observations of the celebrities right now.
Yutaka Hirai of Tohoku College commented:
The gold-rich stars right now inform us the historical past of the Milky Way. We discovered most gold-rich stars are shaped in dwarf galaxies over 10 billion years in the past. These historic galaxies are the constructing blocks of the Milky Way.
Our findings imply lots of the gold-rich stars we see right now are the fossil data of the Milky Way’s formation over 10 billion years in the past.
And he added:
Comparability with simulations and observations within the Milky Way opens a brand new avenue for extracting the fossil data of stars.
Backside line: New pc simulations are displaying that almost all gold-rich stars have been shaped in low-mass dwarf galaxies that merged with our Milky Way galaxy some 10 billion years in the past.
