Galaxies are gravitationally bound, large-scale astrophysical systems composed primarily of dark matter, stars, stellar remnants, gas, and dust, often embedded in extended dark matter halos. They exhibit diverse morphologies, including spiral, elliptical, and irregular types, and span mass scales from roughly 10⁷ to over 10¹² solar masses. Their internal dynamics are governed by gravity and angular momentum distribution, with baryonic components organized into disks, bulges, and halos, and frequently hosting central supermassive black holes. Galaxies are fundamental units of cosmic structure formation, participating in hierarchical assembly, mergers, and interactions within larger environments such as groups, clusters, and filaments of the cosmic web.
The Sloan Digital Sky Survey (SDSS), the largest multispectral imaging and spectroscopic redshift survey of the cosmos, has released its 20th data release (DR 20). It is also the third release of the survey's fifth phase ...
Astronomy
Sep 7, 2026
0
38
The universe has been having fewer and fewer stellar "babies." Over the past 4.5 billion years, the rate of star birth has crashed to less than half of what it once was. But here's the twist: the most essential "fuel" for ...
Astronomy
Sep 1, 2026
0
49
NASA's newest crown jewel blasted off Sunday to hunt for planets around other stars, explore secret dark energy and survey the cosmos like never before.
Astronomy
Aug 30, 2026
0
75
In dark skies at night, distant starlight twinkles and speaks to vast cosmic histories almost as old as time itself. New data from instruments such as NASA's James Webb Space Telescope are helping astrophysicists probe deep ...
Astronomy
Aug 27, 2026
0
38
The latest Swedish-led search for technosignatures in the form of Dyson spheres has again come up empty-handed. The two latest stellar candidates in the hunt for such hypothetical extraterrestrial technology have been eliminated ...
Astronomy
Aug 27, 2026
0
89
Galaxies are like cosmic gems, each with characteristics including size and shape that make them distinct. A new gallery released today from NASA's Chandra X-ray Observatory and other telescopes displays a collection of galactic ...
Astronomy
Aug 25, 2026
0
464
Little red dots may reside in small, dense galaxies with total masses equivalent to around 1 billion times that of the sun, according to research published in Nature Astronomy.
Astronomy
Aug 25, 2026
2
75
University of Missouri researchers have uncovered evidence that challenges one of astronomy's most trusted assumptions, a breakthrough that could reshape how scientists measure galaxies and reconstruct the history of the ...
Astronomy
Aug 11, 2026
6
93
Since it became operational in 2022, the James Webb Space Telescope (JWST) has released some truly breathtaking views of the cosmos. These images highlight how advancements since the days of the venerable Hubble Space Telescope ...
Astronomy
Aug 10, 2026
1
182
The origin of spin in spiral and elliptical galaxies has posed a long-standing puzzle for astronomers. One idea, known as tidal torque theory, proposes that galaxies' spins are an imprinted record of the early universe, imparted ...
