Galaxies Content

Simulations Explain Abundance of Bright Galaxies at Cosmic Dawn

Andy Fell — October 03, 2023 - 12:41pm

When researchers glimpsed the first images and data from the James Webb Space Telescope (JWST), humanity’s largest and most powerful space telescope, they noticed something peculiar. A large number of bright galaxies deep in the universe formed during a period called “Cosmic Dawn,” when the first stars and galaxies formed within 500 million years after the Big Bang.

Making Better Measurements of the Composition of Galaxies

Andy Fell — April 20, 2023 - 8:00am

A study using data from telescopes on Earth and in the sky resolves a problem plaguing astronomers working in the infrared and could help make better observations of the composition of the universe with the James Webb Space Telescope and other instruments. The work is published April 20 in Nature Astronomy.

Newly Discovered Gravitational Lenses Could Reveal Ancient Galaxies and the Nature of Dark Matter

Andy Fell — September 29, 2022 - 4:38pm

An international team of astronomers has discovered dozens of strong gravitational lenses that will allow astronomers to look deep into the universe, revealing ancient structures and giving insight into the nature of dark matter.

Taking the Temperature of Dark Matter

Andy Fell — January 15, 2020 - 9:24am

Warm, cold, just right? Physicists at the University of California, Davis, are taking the temperature of dark matter, the mysterious substance that makes up about a quarter of our universe.

We have very little idea of what dark matter is, and physicists have yet to detect a dark matter particle. But we do know that the gravity of clumps of dark matter can distort light from distant objects. Chris Fassnacht, a physics professor at 51�ԹϺ�� Davis, and colleagues are using this distortion, called gravitational lensing, to learn more about the properties of dark matter.

Astronomers Find a Cosmic Titan in the Early Universe

Andy Fell — October 17, 2018 - 8:55am

An international team of astronomers has discovered a titanic structure in the early universe, just 2 billion years after the Big Bang. This galaxy proto-supercluster, nicknamed Hyperion, is the largest and most massive structure yet found at such a remote time and distance.

Astronomers Spy Supernova’s Giant Companion Star

Kimberly L Hale — August 14, 2017 - 4:48pm

Astronomers have spied the short-lived blue glow from a giant companion star struck by a spectacular supernova. The discovery offers compelling evidence for a leading theory about the origin of Type Ia supernovae — that these enormous explosions occur when a white dwarf steals matter from a larger star.

Long Ago and Far Away, an Average Galaxy

Andy Fell — April 10, 2017 - 8:00am

Astronomers led by a graduate student at the University of California, Davis have discovered one of the most distant galaxies in the universe, and it’s nothing out of the ordinary.

Astronomers Measure Universe Expansion, Get Hints of ‘New Physics’

Andy Fell — January 26, 2017 - 5:01pm

Astronomers have just made a new measurement of the Hubble constant, the rate at which the universe is expanding, and it doesn’t quite line up with a different estimate of the same number. That discrepancy could hint at “new physics” beyond the standard model of cosmology, according to the team, which includes physicists from the University of California, Davis, that made the observation.

Astronomers See Faintest, Furthest Galaxy

Andy Fell — May 19, 2016 - 12:19pm

A team of scientists led by two 51�ԹϺ�� Davis physicists has detected and confirmed the faintest early-universe galaxy yet. This new object, seen as it was about 13 billion years ago, could help astronomers understand the “reionization epoch” when the first stars became visible.