Taking the Temperature of Dark Matter

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.

Explaining the Tiger Stripes of Enceladus

Saturn’s tiny, frozen moon Enceladus is a strange place. Just 300 miles across, the moon is thought to have an outer shell of ice covering a global ocean 20 miles deep, encasing a rocky core. Slashed across Enceladus’ south pole are four straight, parallel fissures or “tiger stripes” from which water erupts. These fissures aren’t quite like anything else in the solar system. 

Astronomers Find a Cosmic Titan in the Early Universe

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.

UC Davis Astronomers Help Uncover the Farthest Star Ever Seen

Through a lucky quirk of nature, astronomers have used the Hubble Space Telescope to view a single star halfway across the universe. Nine billion light years from Earth, the giant blue-white star, nicknamed “Icarus” by the team, is by far the most distant individual star ever seen. Marusa Bradac, a physics professor and astronomer at UC Davis and graduate student Austin Hoag are part of the team describing Icarus and another distant, magnified star in two papers published April 2 in the journal Nature Astronomy.

Doing Without Dark Energy

Mathematicians Blake Temple and Zeke Vogler at the University of California, Davis, and Joel Smoller at the University of Michigan, Ann Arbor, worked out solutions to General Relativity without invoking dark energy. They argue that the equations show that the Friedmann space-time is actually unstable: Any perturbation — for example if the density of matter is a bit lower than average — pushes it over into an accelerating universe.

UC Davis Helps Spot Colliding Neutron Stars, An Astronomical Breakthrough

For the first time, astronomers have observed a celestial event through both conventional telescopes and gravitational waves. Assistant Professor Stefano Valenti helped detect the collision of two neutron stars and confirm these cataclysmic events are the source of gold, platinum and other heavy elements.

Astronomers See Faintest, Furthest Galaxy

A team of scientists led by two UC 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.