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.
Yale astronomer Pieter van Dokkum and a team of researchers have discovered an object in space they call the "Infinity" galaxy—two recently-collided galaxies that, together, look like the symbol for infinity.
Astronomy
Jul 15, 2025
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Dark matter is one of nature's most confounding mysteries. It keeps particle physicists up at night and cosmologists glued to their supercomputer simulations. We know it's real because its mass prevents galaxies from falling ...
Astronomy
Jul 12, 2025
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Names are a strange thing in astronomy. Sometimes scientists come up with grandiose, simple name, like the Extremely Large Telescope. Other times, they come up with unique sounding names, like quasars. And sometimes they ...
Astronomy
Jul 10, 2025
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Celestial objects known as dark dwarfs may be hiding at the center of our galaxy and could offer key clues to uncover the nature of one of the most mysterious and fundamental phenomena in contemporary cosmology: dark matter.
Astronomy
Jul 7, 2025
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When it comes to star formation, not all galaxies are the same. Some are quenched, meaning they've depleted their star forming gas and form very few new stars. Some, like the Milky Way, are typical and form stars at an average ...
Astronomy
Jul 3, 2025
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Astronomers have used the Atacama Large Millimeter/submillimeter Array (ALMA) to peer into the early universe and uncover the building blocks of galaxies during their formative years. The CRISTAL survey—short for [CII] Resolved ...
Astronomy
Jul 2, 2025
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A new result from the molecular gas survey in the Southern Pinwheel Galaxy M83 using the Atacama Large Millimeter/submillimeter Array (ALMA) Telescope reveals a discovery of 10 high-velocity clouds composed of molecular gas, ...
Astronomy
Jul 1, 2025
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Astronomers have uncovered a vast cloud of energetic particles—a "mini halo"—surrounding one of the most distant galaxy clusters ever observed, marking a major step forward in understanding the hidden forces that shape the ...
Astronomy
Jun 26, 2025
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Disk galaxies, like our own Milky Way galaxy, commonly consist of both a thick and thin disk of stars—each with different features, including stellar population and movement. Three major theoretical scenarios have been proposed ...
Astronomy
Jun 26, 2025
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This portrait from the NASA/ESA Hubble Space Telescope puts the nearby galaxy NGC 4449 in the spotlight. The galaxy is situated just 12.5 million light-years away in the constellation Canes Venatici (the Hunting Dogs). It ...
Astronomy
Jun 23, 2025
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