Astronomy

Both are low-probability but catastrophic events—and both can be mitigated if we act early enough

Astronomers have observed record-breaking photons that strain classical theories of acceleration

The huge object may be the biggest comet ever seen. And it is already showing signs of activity as it approaches the orbit of Saturn

Circumstantial evidence could point to a mind-blowing solution to an antimatter mystery—or to the need for better space-based particle physics experiments

New radio-based observatories could soon detect ultrahigh-energy neutrinos, opening a new window on extreme cosmic physics

Images from the Event Horizon Telescope reveal new details of how supermassive black holes produce huge jets of matter and energy

Astronomers are hunting for the first moon around a planet beyond our solar system

Recent results from a pulsar timing array, which uses dead stars to hunt for gravitational waves, has scientists speculating about cosmic strings and primordial black holes

Large galaxies are thought to form gradually, across billions of years of cosmic time. So why do astronomers keep finding them in the youthful early universe?

A new analysis of light and gravitational waves from colliding neutron stars helps reveal what’s inside these ultradense objects

The enigmatic origins of chondrules—tiny inclusions in most meteorites—may be revealed at last, thanks in part to pristine material returned to Earth from asteroid Ryugu

Astrophysicists now have enough black-hole mergers to map their frequency over the cosmos’s history