All articles tagged with #metal poor
A student-led team at the University of Chicago, using Sloan Digital Sky Survey data, discovered SDSS J0715-7334 — a nearly metal-free ancient star that originated in the Large Magellanic Cloud and later drifted into the Milky Way, offering a rare glimpse into the early universe.
A University of Chicago undergraduate team using Sloan Digital Sky Survey data identified SDSSJ0715-7334 as an ultra-pristine, extremely metal-poor star (0.005% of the Sun’s metals) that likely formed in the Large Magellanic Cloud before migrating into the Milky Way; Gaia data confirms its past orbit and its carbon is undetectable, offering a rare glimpse into the conditions of the early universe.
Astronomers have identified PicII-503, an extremely iron-poor Population II star in the ultra-old dwarf galaxy Pictor II, about 150,000 light-years away. Its iron abundance is about 43,000 times lower than the Sun and calcium about 160,000 times lower, while its carbon is vastly enriched, suggesting it formed from gas enriched by the very first stars. As the most iron-poor star found outside the Milky Way, PicII-503 offers a rare glimpse into early nucleosynthesis and the remnants of Population III stars; it was discovered via the MAGIC survey using the Dark Energy Camera and is reported in Nature Astronomy.
Scientists using the Dark Energy Camera identified PicII-503, an iron-poor second-generation star in the ultra-faint dwarf galaxy Pictor II, with iron about 1/40,000 that of the Sun and a carbon overabundance, providing a fossil record of how the first stars enriched later generations and shedding light on primordial element production in the early universe.
Astronomers have discovered supernova 2023ufx, the most metal-poor stellar explosion observed, in a dwarf galaxy. This finding provides insights into the early universe's conditions, aiding in understanding galaxy formation and evolution. The supernova's unique properties, such as its rapid brightness decline and fast-moving ejected material, suggest that rapidly spinning metal-poor stars were common in the early universe. The discovery, facilitated by advanced instruments like the James Webb Space Telescope, offers a benchmark for future studies on metal-poor stars and cosmic evolution.
Using the Southern African Large Telescope (SALT), astronomers have discovered EC 19529−4430, the most metal-poor extreme helium star known to date, located in the Galactic halo about 15,500 light years away. The star's surface is primarily composed of carbon-nitrogen-oxygen-processed helium, and it is the coolest known carbon-poor and nitrogen-rich extreme helium star. Researchers believe it likely formed from the merger of two helium white dwarfs and will evolve into a core helium-burning EHe subdwarf.
Astronomers have discovered a new star cluster, DELVE 6, which is ultra-faint, metal-poor, and estimated to be about 9 billion years old. It is located in the outskirts of the Magellanic Clouds, beyond the tidal radius of the Large Magellanic Cloud due to the Milky Way and the tidal radius of the Small Magellanic Cloud due to the Large Magellanic Cloud. DELVE 6 may be only the second or third ancient star cluster associated with the Small Magellanic Cloud or one of fewer than two dozen ancient clusters associated with the Large Magellanic Cloud.