Cosmology

Artist's concept of a neutron star emitting a fast radio burst from its magnetosphere (Image courtesy Daniel Liévano, edited by MIT News)

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An article published in the journal “Nature” reports the identification of the origin of the fast radio burst cataloged as FRB 20221022A linking it to a magnetar-class neutron star, probably emerging from its magnetosphere. A team of researchers coordinated by MIT used observations conducted with the CHIME radio telescope to identify the origin of this already-known fast radio burst by exploiting the phenomenon of scintillation, comparable to how stars twinkle in the sky. This is further evidence of the link between magnetars and fast radio bursts, the very powerful emissions that can be one-time or repeated events.

A group of galaxies observed by the James Webb Space Telescope (Image NASA, ESA, CSA)

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An article published in “The Astrophysical Journal” reports the results of a new measurement of the universe’s expansion rate obtained using observations conducted with the James Webb Space Telescope that confirms previous results obtained with Hubble. A team of researchers led by Adam Riess, who has been investigating the expansion of the universe for years, verified that the so-called Hubble tension, as the discrepancy between different measurements is called, was not due to limitations of the Hubble Space Telescope. According to Riess, this result confirms that our cosmological models are incomplete and there may be something we don’t yet understand about the universe.

The ultramassive galaxies S1, S2, and S3

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An article published in the journal “Nature” reports the discovery of three ultramassive galaxies in the early universe in which stars are forming with an efficiency almost twice that of galaxies of average mass by the standards of that era. A team of researchers coordinated by the University of Geneva (UNIGE) used observations conducted with the James Webb space telescope within the FRESCO program. The three galaxies (Image NASA/CSA/ESA, M. Xiao & P. ​​A. Oesch (University of Geneva), G. Brammer (Niels Bohr Institute), Dawn JWST Archive), which were cataloged as S1, S2, and S3, are almost as massive as the Milky Way and add to others that were discovered in recent years and are difficult to explain with the most accepted cosmological models, starting with lambda-CDM.

Protogalaxies as seen by the James Webb Space Telescope (Image NASA)

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An article published in “The Astrophysical Journal” reports some predictions offered by MOND (Modified Newtonian Dynamics), a theory based on modifications to Newton and Einstein’s gravitational laws that doesn’t include the existence of dark matter. Stacy S. McGaugh, James M. Schombert, Federico Lelli, and Jay Franck have applied this model to primordial galaxies studied with the James Webb Space Telescope obtaining a better agreement than the lambda-CDM model, the best cosmological model based on the existence of dark matter. This is one of the studies, often based on Webb’s observations, that are testing cosmological models that weren’t considered very much due to the lack of confirmation.

The Hubble Ultra Deep Field with an inset that shows a magnification of two primordial galaxies, one of which contains a supermassive black hole

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An article published in “The Astrophysical Journal Letters” reports the results of a census of the youngest supermassive black holes that existed in the early universe. A team of researchers used observations conducted with the Hubble Space Telescope that started from the so-called Hubble Ultra Deep Field to search for primordial supermassive black holes with the addition of data recently collected using the James Webb Space Telescope. The conclusion is that these objects are more numerous than expected, a confirmation that they formed very quickly. This new study will help to understand how.