A new study casts doubt on the universe’s accelerating expansion, suggesting dark energy might be weakening over time.

A new set of computer simulations may finally explain several long-standing mysteries surrounding gigantic radio "relics" ...

Chinese researchers have identified black holes as the likely source of the high-energy component of the cosmic-ray “knee.” Milestone findings released on November 16 by the Large High Altitude Air Sh ...

The observations are the earliest yet of a supernova, revealing in detail the moment that the shockwave obliterated the star.

Over the course of billions of years, the universe has steadily been evolving. Thanks to the expansion of the universe, we ...

Astornmers have found the coldest spot in the universe. Where it's located came as a surprise. Experts watch this frost zone ...

The distant universe might be littered with supermassive stars between 1000 and 10,000 times the mass of the sun, which could ...

The powerful coronal mass ejection would have likely destroyed the atmospheres of any potentially habitable planets nearby ...

Astronomers generally assume that active galaxies may shift and flicker, since their central supermassive black holes tend to ...

Astronomers at the University of Arizona’s Steward Observatory, led by Kevin Wagner, have identified evidence for a potential ...

JWST has detected rare silane gas in an ancient, oxygen-poor brown dwarf, revealing a key clue to why Jupiter and Saturn hide ...

European Space Agency says milestone highlights both Earth’s vulnerability and advances in planetary-defense science - ...