Astrophysics

Cosmic Microwave Background Stage 4, a top-priority project for U.S. astrophysics, was designed to make breakthrough observations of the universe’s very earliest moments. Now the U.S. government says it can’t currently support the project’s construction at the South Pole

A supernova showering Earth with radioactive debris is a surprisingly common cosmic occurrence

For the first time, scientists observed matter’s free fall into a black hole’s “plunging region”

How do astronomers find the darkest objects in the universe?

An exploding star is a catastrophe on a cosmic scale, but here on Earth we’re safe from such astral disasters—for now

The far side of the moon holds the keys to the future of radio astronomy. We must maintain its pristine silence to benefit everyone

Every now and then, tiny particles of antimatter strike Earth from cosmic parts unknown. A new balloon-borne experiment launching this spring may at last find their source

Domain walls, long a divisive topic in physics, may be ideal explanations for some bizarre cosmic quirks

Someday an unlucky outburst from our sun could strike Earth and fry most of our electronics—and we’ve already had some too-close-for-comfort near misses

Perspective and subtle motion allows us to peek over the moon’s edge and into its far side

As the Event Horizon Telescope pursues ambitious upgrades, the project’s latest results reveal the magnetic fields around our galaxy’s supermassive black hole

In just one year of observations, a program that is creating the largest 3D map of the universe to date has sniffed out hints that dark energy may be stranger than scientists supposed