Exciting new findings reveal that the star SDSS J0715-7334, formed in the halo of the Large Magellanic Cloud, migrated to the Milky Way billions of years ago, as uncovered by a dedicated team of undergraduate students at the University of Chicago.
Milky Way Galaxy illustrating the position of SDSS J0715-7334. The red line represents the star’s path, while the blue line indicates the expected trajectory for stars formed in the Large Magellanic Cloud. Image credits: Vedant Chandra / SDSS Collaboration / ESA / Gaia / A. Moitinho, AF Silva, M. Barros, C. Barata, University of Lisbon / H. Savietto, Fork Research.
The Big Bang initiated the universe, creating a hot, dense soup of energetic particles.
As the universe expanded, this primordial material cooled, leading to the formation of neutral hydrogen gas.
Denser regions of this gas collapsed under gravity after hundreds of millions of years, resulting in the birth of the universe’s first stars made of hydrogen and helium.
These ancient stars burned brightly but lived fast, generating heavier elements through nuclear fusion, which were dispersed into the cosmos upon their explosive deaths.
This enriched material then contributed to the formation of subsequent stars that were diverse in their elemental composition.
“Heavy elements, referred to as metals by astronomers, were produced through stellar activities, including nuclear fusion and supernova blasts,” noted Alex Gee, a professor at the University of Chicago.
“The discovery of a star with extremely low metal content indicated to the students that they had found something extraordinary.”
SDSS J0715-7334 is remarkable, containing only 0.005% of the metal content found in our Sun, making it the least metallic star ever recorded, surpassing the previous record holder by over double.
This star, identified using data from the Sloan Digital Sky Survey (SDSS), is located approximately 80,000 light-years from Earth.
Its orbital analysis confirms its origin in the Large Magellanic Cloud, from where it journeyed into the Milky Way billions of years ago.
“This ancient celestial traveler provides invaluable insights into the conditions of the early universe,” said Professor Gee.
“Big data initiatives like SDSS empower students to take part in groundbreaking discoveries.”
“We studied a variety of elements within this star, and we found all of them to have very low abundances,” explained Ha Do, one of the University of Chicago students involved in the discovery.
The team’s research paper is published in the journal Nature Astronomy.
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AP via others. A near-primitive star from the Large Magellanic Cloud. Nat Astron published online on April 3, 2026. doi: 10.1038/s41550-026-02816-7
Source: www.sci.news
