Astrophysics

Scientists haven’t tested the Big Bang’s light for a revealing shift in 25 years. A new experiment aims to change that.

Physicists are beginning to unravel the mysteries of ultrahigh-energy cosmic rays, particles accelerated by the most powerful forces in the universe.

Nature has revealed peculiar mathematical objects that connect order and chaos.

No definitive evidence for cosmic inflation is found, but support remains strong for the theory even as critics highlight its shortcomings as an explanation for how and why the universe began.

For five years physicists have been tantalized by possible evidence of dark matter in the Milky Way’s center. But new results from small satellite galaxies have complicated the story.

Cosmic dust in the high latitudes of the Milky Way could account for the entire swirl pattern that had been presented as proof of a leading Big Bang theory, according to a new data analysis from the Planck satellite.

The astrophysicist Joshua Frieman seeks to pinpoint the mysterious substance driving the accelerating expansion of the universe.

Katherine Freese, a physicist who will soon lead the Nordic Institute for Theoretical Physics, reflects on the hunt for dark matter and how dark matter heating may have produced the first stars.

A new analysis strengthens the case that gamma rays emanating from the center of the Milky Way come from dark matter particles known as WIMPs.