'Ghost towns' of the universe: Ultra-faint, rare dwarf galaxies offer clues to the early cosmos
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Updates every hour. Last Updated: 27-Jun-2025 01:10 ET (27-Jun-2025 05:10 GMT/UTC)
Astronomers have struggled with finding ultra-faint dwarf galaxies far enough from the Milky Way's influence, making these faintest galaxies in the cosmos difficult to study. Three newly discovered dwarf galaxies in an isolated region of space show evidence of star formation being cut short by events in the early universe.
New Haven, Conn. — A Yale-led team of astronomers has detected an intensely brightening and dimming quasar that may help explain how some objects in the early universe grew at a highly accelerated rate.
The discovery, announced Jan. 14 at the winter meeting of the American Astronomical Society, is the most distant object detected by the NuSTAR X-ray space telescope (which launched in 2012) and stands as one of the most highly “variable” quasars ever identified.
“In this work, we have discovered that this quasar is very likely to be a supermassive black hole with a jet pointed towards Earth — and we are seeing it in the first billion years of the universe,” said Lea Marcotulli, a postdoctoral fellow in astrophysics at Yale and lead author of a new study published Jan. 14 in The Astrophysical Journal Letters.
SAN ANTONIO — January 15, 2025 —Southwest Research Institute’s Dr. Lisa Upton has received the 2025 Karen Harvey Prize from the American Astronomical Society’s Solar Physics Division, which recognizes the outstanding contributions made by early career solar scientists. Upton was honored for advancing our understanding of the Sun and exceptional leadership in the solar science community.
For humans, the most important star in the universe is our Sun. The second-most important star is nestled inside the Andromeda galaxy. Don't go looking for it — the flickering star is 2.2 million light-years away, and is 1/100,000th the brightness of the faintest star visible to the human eye.
Yet, a century ago, its discovery by Edwin Hubble, then an astronomer at Carnegie Observatories, opened humanity's eyes as to how large the universe really is, and revealed that our Milky Way galaxy is just one of hundreds of billions of galaxies in the universe ushered in the coming-of-age for humans as a curious species that could scientifically ponder our own creation through the message of starlight. Carnegie Science and NASA are celebrating this centennial at the 245th meeting of the American Astronomical Society in Washington, D.C.
Hot Jupiters are giant planets initially known to orbit alone close to their star. During their migration towards their star, these planets were thought to accrete or eject any other planets present. However, this paradigm has been overturned by recent observations, and the final blow could come from a new study led by the University of Geneva (UNIGE). A team including the National Centre of Competence in Research (NCCR) PlanetS, the Universities of Bern (UNIBE) and Zurich (UZH) and several foreign universities has just announced the existence of a planetary system, WASP-132, with an unexpected architecture. It not only contains a Hot Jupiter but also an inner Super-Earth and an icy giant planet. These results are published in Astronomy & Astrophysics.