Jonathan O'Callaghan

Over the past decade, researchers have completely rewritten the story of how gas giants such as Jupiter and Saturn form. They’re now debating whether the same process might hold for Earth.

After a search of neutron stars finds preliminary evidence for hypothetical dark matter particles called axions, astrophysicists are devising new ways to spot them.

Brown dwarfs such as “The Accident” are illuminating the murky borderlands that separate planets from stars.

These ultrabright flashes have recently been tracked for days, upending ideas about the cataclysms that create them.

Groundbreaking results show that neutron stars of different masses may have the same size — upending astrophysical models.

The thorny thought experiment has been turned into a real experiment — one that physicists use to probe the physics of information.

Black holes seemed to come only in sizes small and XXL. A new search strategy has uncovered a black hole of “intermediate” mass, raising hopes of more to come.

A supernova-like explosion dubbed the Camel appears to be the result of a newborn black hole eating a star from the inside out.

A new study shows that extreme black holes could break the famous “no-hair” theorem, and in a way that we could detect.