Tag

Galaxies

All articles tagged with #galaxies

science1 day ago•4 min saved

Webb dots reveal early supermassive black holes in tiny galaxies

A Nature Astronomy study using JWST data from the COSMOS-Web region suggests the mysterious 'little red dots' are the earliest supermassive black holes, residing in very compact host galaxies that contain about 1 billion stars. The host galaxies are ~4% of the Milky Way’s size and contribute only ~10% of the dots’ light, while the central black holes (roughly 10^7–10^9 solar masses) dominate the emission. This implies black holes may grow most of their mass before their galaxies form most of their stars, shedding light on how black holes and galaxies co-evolve; the team analyzed 217 JWST images across a region about three times the Moon’s size to measure host properties and applied PSF subtraction to isolate the faint hosts.

via The Conversation|

#astronomy #black-holes #early-universe

science1 day ago•2 min saved

Hidden Low-Mass Stars Make Early Massive Galaxies Much Heavier Than Thought

Webb Space Telescope observations (with VLT data) published in Nature Astronomy reveal a hidden population of small, faint stars in nine of the universe’s most massive early galaxies, implying those systems are far more massive than previously estimated. By analyzing subtle spectral signatures of low-mass stars, researchers found many more dwarfs than bright stars alone would suggest, with one galaxy formed within roughly 1.5 billion years after the Big Bang potentially four times heavier than thought. This challenges existing models of early galaxy growth and could have implications for planet formation around low-mass stars in the ancient universe.

via Gizmodo|

#astronomy #early-universe #galaxies

space12 days ago•206 min saved

Cosmic breadcrumb: first globular-cluster stellar stream spotted beyond the Milky Way

Astronomers discovered the first globular-cluster stellar stream outside the Milky Way, in a galaxy about 115 million light-years away, by analyzing archival data from the Hubble Space Telescope. The faint stellar trail reveals the host galaxy's gravitational field and total mass, offering a new way to map dark matter and understand how galaxies form and evolve across the universe.

via CNN|

#dark-matter #galaxies #globular-clusters

space-and-spaceflight13 days ago•18 min saved

Astronomers Uncover a Black Hole Star in the Early Universe

Nature-published researchers report the discovery of MoM-BH*-1, a newly identified object that resembles a giant star but radiates energy like a black hole, wrapped in dense gas and outshining its host galaxy. Scientists label it a “black hole star,” a find that could illuminate how the first supermassive black holes formed and connect to the JWST-detected little red dots from the cosmic dawn; further JWST observations are planned to constrain its mass and atmospheric properties.

via Gizmodo|

#black-hole-star #early-universe #galaxies

space15 days ago•157 min saved

Andromeda's Star Formation Slows, Suspected Trigger: a Neighbor Named M32

Hubble observations show the Andromeda galaxy’s rate of turning gas into stars has dramatically slowed in the last ~40 million years, with the slowdown most pronounced on the side facing its tiny neighbor M32. While researchers acknowledge they can’t prove M32 caused the decline, it is the leading suspect, possibly due to a past collision. The study mapped Andromeda’s history across two-thirds of its disk, finding current star formation at about 0.2 solar masses per year (roughly one-fifth the Milky Way’s rate). The Nancy Grace Roman Space Telescope will help measure more of Andromeda’s stars to further test the M32-link in the coming years.

via Space|

#andromeda #galaxies #hubble-space-telescope

science20 days ago•3 min saved

Rubin Observatory Debuts Deep-Sky Mosaic Covering 500,000 Galaxies

The Rubin Observatory released its first science image from the LSST, a deep view of the COSMOS field featuring more than 500,000 galaxies (and about 50,000 foreground stars) captured with the 3.2-gigapixel LSST Camera. Part of Early Data Preview 2, the image previews the decade-long Legacy Survey of Space and Time and will be followed by repeated observations to study galaxy evolution and transient events like supernovae, building what scientists describe as the most comprehensive cinematic record of the universe.

via The Debrief|

#astronomy #cosmos-field #galaxies

science22 days ago•3 min saved

Rubin Observatory Captures 650,000 Galaxies in a Single COSMOS View

A new Rubin Observatory image of the COSMOS field captures more than 650,000 galaxies and 50,000 stars in a single deep view, thanks to its 3.2-gigapixel camera. Rubin will image this patch repeatedly over its decade-long LSST survey, enabling comparisons with Hubble and Webb and advancing studies of dark matter, dark energy, supernovae, and near-Earth asteroids.

via Gizmodo|

#astronomy #cosmos-field #galaxies

space23 days ago•5 min saved

Rubin Observatory Unveils 500,000+ Galaxies in a 3.2-Gigapixel COSMOS Deep Field

Rubin Observatory’s 3.2-gigapixel LSST camera captured a deep-field image of the COSMOS patch, stacking hundreds of exposures to reveal more than half a million galaxies as the telescope begins its decade-long mission to repeatedly image the sky and study galaxy evolution and transient phenomena.

via PetaPixel|

#astronomy #cosmos-field #galaxies

space1 month ago•10 min saved

Ten Space Revelations Redraw the Cosmos

Ten recent space discoveries—ranging from neon hints of Mars’ recent volcanism and the mature early galaxy Zhúlóng seen by JWST, to newborn planets around PDS 70 and a possible fifth world near L 98-59—demonstrate how JWST and Hubble are reshaping our understanding of planet formation, galaxy evolution, and cosmic history, while prompting new views on the Milky Way–Andromeda fate and the Sun’s distant future.

via Listverse|

#cosmology #exoplanets #galaxies

space-and-spaceflight1 month ago•17 min saved

Missing Ordinary Matter Reunited: Diffuse Gas Envelopes Galaxies and Clusters

Using thousands of fast radio burst measurements, researchers mapped where ordinary (baryonic) matter resides and found widespread, diffuse gas surrounding galaxies and galaxy clusters. This diffuse gas accounts for the universe’s missing baryons, extending up to about 4 million light-years from galaxies and suggesting energetic processes like black hole jets fling baryons far beyond visible halos, which helps reconcile observations with current astrophysical models.

via Gizmodo|

#baryons #diffuse-gas #fast-radio-bursts

science1 month ago•13 min saved

AI sifts through Hubble archive in 2.5 days, flags 1,339 unusual sources, 811 with no literature reference

A machine-learning system called AnomalyMatch scanned about 99.6 million Hubble image cutouts in roughly two and a half days, ranking rare morphologies and surfacing 1,339 unusual sources. Literature checks found 811 with no prior reference; after human review the team distilled to 147 strong outliers, illustrating how AI can rapidly triage vast archives and move rare astronomical structures toward expert study rather than acting as an autonomous discoverer.

via Space Daily|

#ai #anomalies #astronomy

space1 month ago•105 min saved

Nearby ravenous black hole mirrors early-universe feeding frenzy

Astronomers observe a supermassive black hole at the center of SDSS J110546.07+145202.4 (about 1.8 billion light-years away) in a rapid accretion phase, launching jets and causing a roughly 20-fold increase in radio brightness over about eight years. The behavior resembles the vigorous feeding seen in the early universe, providing a nearby laboratory to study extreme accretion physics and jet production. The finding, published in The Astrophysical Journal (May), suggests such rapidly changing radio galaxies could help fill gaps in our understanding of early galaxy growth, with future SKA surveys expected to identify more transients.

via Space|

#accretion #black-holes #early-universe

space1 month ago•6 min saved

Giant Unexplained Radio Rings Hint at a New Class of Cosmic Structures

Astronomers have identified eight gigantic rings of radio emission in deep space, each more than 50 times the Milky Way’s width and visible only at radio wavelengths; their origins are unknown, though three rings sit at galaxy centers, suggesting the rings may be produced by galactic activity and could represent a new class of astronomical objects.

via Boing Boing|

#galaxies #new-class-of-astronomical-objects #odd-radio-circles

space1 month ago•6 min saved

Cosmic Web Persists Across Vast Scales, Challenging Uniformity

A Nature study analyzing 47 million galaxies from the DESI survey finds coherent patterns in the cosmic web extending across billions of light-years, suggesting the universe may not be perfectly homogeneous or isotropic on the largest scales. The result challenges a key cosmological assumption and could prompt revisions to models of dark matter, gravity, and structure formation, though independent replication with larger datasets is needed before firm conclusions.

via WIRED|

#astronomy #cosmic-web #cosmology

space1 month ago•14 min saved

Hubble’s Dark Patch Reveals a Crowded Cosmos: 3,000 Galaxies in a Tiny Sky

In 1995, the Hubble Space Telescope fixed its gaze on a seemingly empty patch of sky for ten days, assembling hundreds of exposures into the Hubble Deep Field and turning a void into a crowded image of roughly 3,000 distant galaxies—each billions of years old—demonstrating that the universe is full of structure even in directions that appear empty and paving the way for deeper surveys with Hubble and Webb.

via Space Daily|

#astronomy #deep-field #galaxies