The abstract states - “Large dust reservoirs (up to ~10^8 M⊙) have been detected in galaxies out to redshift z ∼ 8, when the age of the universe was only about 600 Myr. IMO, that would suggest problems in the 4 stages of the cosmic fireball evolution (heavy particle, light particle, radiation era, matter era) developed to explain the presence and origin of the CMBR in the BB model. Perhaps there never was pristine, metal free gas in the Universe and JWST is finding this, lack of evidence for the metal free gas during BBN and the cosmic dark ages in the BB model. The JWST is the most sensitive infrared space telescope ever placed into space and the only one capable of resolving features like these carbon fingerprints in the light from such distant galaxies.Ī very interesting report and the reference provided, 33-page PDF to study. Light from these galaxies has been crossing the cosmos for as long as 12.8 billion years and is now infrared light. This results in ultraviolet light from galaxies being shifted down the electromagnetic spectrum, a process called " redshift." The more distant, and thus earlier, the galaxy, the more extreme the redshift is, meaning light from the very first galaxies is stretched out to infrared wavelengths. The wavelengths of light emitted by early galaxies are stretched by the universe's expansion as it travels across billions of light years, thus taking billions of years to reach us. The findings exemplify the kind of science that wouldn't have been possible before the JWST, which began observing the universe and delivering data and images in July 2022. That implies there must be a creation and dispersal method for carbon that works on a relatively short time scale. This is challenged by the findings reached by Witstok and colleagues as some of the galaxies they saw PAH dust in are estimated to be somewhere in the region of 10 million years old. When dense patches of this dust collapse, this material becomes the building blocks of the next generation of stars, which are thus richer in heavy elements and sit in similarly enriched galaxies. This stellar matter is integrated into interstellar dust. When the first stars ran out of the fuel for nuclear fusion and reached the end of their lives, they exploded in supernovas dispersing the material they had forged through the cosmos. The early universe was made up of mostly hydrogen and helium with tiny traces of some heavier elements, meaning the first stars and galaxies should have the same composition of just these light elements.Ĭonventional models of the universe's chemical evolution suggest that heavy elements like carbon and oxygen are forged in the nuclear furnaces at the heart of stars. The question is, how did these young galaxies get enriched with carbon so quickly? A cosmic "get rich quick" scheme? The aromatic hydrocarbon dust was given away by a 'bump' in the absorption of specific ultraviolet frequencies of light. Detections like this are possible because elements absorb and emit light at characteristic wavelengths meaning they leave their "fingerprints" in light from sources such as galaxies and stars. The team spotted this carbon dust in this sample of ten galaxies by examining the light spectrum from them as part of the JWST Advanced Deep Extragalactic Survey (JADES).
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