When you buy through links on our articles, Future and its syndication partners may earn a commission.Stars in the faint dwarf galaxy Pictor II home of PicII-503 an iron deficient second generation star. | Credit: CTIO/NOIRLab/DOE/NSF/AURAImage processing: Image Processing: T.A. Rector (University of Alaska Anchorage/NSF NOIRLab), M. Zamani & D. de Martin (NSF NOIRLab)Acknowledgment: PI: Anirudh Chiti, Alex Drlica-WagnerScientists have adopted the role of “cosmic archaeologists” to discover a rare, iron-deficient second-generation star — essentially a fossil record of our universe’s chemical evolution. Just as uncovering artifacts here on Earth teaches us about lost generations of humans, this observation provides hard evidence of how the first generation of stars died to chemically enrich their successors.The second generation, or POP II, star was discovered in the dwarf galaxy Pictor II, located around 150,000 light-years from Earth in the constellation Pictor, using the Dark Energy Camera (DECam) mounted atop Víctor M. Blanco 4-meter Telescope. Designated PicII-503, the star has only 1/40,000th of the iron contained within the sun, which is a third-generation, or (somewhat confusingly) POP I, star. The fact that PicII-503 has the lowest concentration of iron ever seen beyond the Milky Way makes it one of the most primordial stars ever discovered.AdvertisementAdvertisementThat deficit isn’t the most extraordinary about PicII-503, however. The team also found that this POP II star has a massive overabundance of carbon, with its ratio of carbon-to-iron over 1,500 times greater than the same ratio in the sun. This overabundance mirrors the unique carbon signature of low-iron stars found in the nebulous outer halo of the Milky Way.”Discoveries like this are cosmic archaeology, uncovering rare stellar fossils that preserve the fingerprints of the universe’s first stars,” Chris Davis, National Science Foundation Program Director for NOIRLab said in a statement.A kind of magicThe first stars in the universe, or POP III stars, were born when the chemical abundance of the cosmos didn’t extend beyond hydrogen, helium, and a smattering of heavier elements, which astronomers collectively call “metals. “This meant that these POP III stars were also dominated by hydrogen with just a littl …
