Astrophysics

Laser-based optical frequency combs, originally developed to time atomic clocks, can also perform fast, noninvasive tests for COVID—and potentially other diseases as well

A dying star swallowing a giant planet hints at the fate awaiting our solar system some five billion years from now

The laws of physics allow time travel. So why haven’t people become chronological hoppers?

A candidate “rogue” supermassive black hole may weigh as much as 20 million suns and has sparked a trail of star formation that is 200,000 light-years long

The “mother of dark matter” was a force of nature—and a forceful advocate for other women who wanted to dedicate their career to the cosmos.

A severe geomagnetic storm created auroras that were visible as far south as Arizona in the U.S.

The “absolutely monstrous” cosmic blast is estimated to be a one-in-10,000-year event

New dedicated observatories and crowdsourced smartphone apps will study strange sightings in the sky. But questionable data quality and a lack of shared research standards remain key challenges

Fireworks display from rare dying star is unlike anything astronomers have seen

The sun is unleashing powerful outbursts that could strike Earth, but these events are far more common—and much less worrisome—than some hyped headlines suggest

For a long time, no one knew how “heavy metals” formed—or showed up on Earth. Now some new evidence finally points the way to an answer.

Growing swarms of spacecraft in orbit are outshining the stars, and scientists fear no one will do anything to stop it