Physicists are quietly entertaining one of the strangest ideas in modern cosmology: that the cosmos we see might be only half ...

Dark matter, one of the Universe’s greatest mysteries, may have been born blazing hot instead of cold and sluggish as ...

The galaxy cluster appears hotter and more mature than it should for its young age, challenging what we think we know about ...

No one knows what kicked off the Big Bang that eventually allowed the stars to begin forming. Adolf Schaller for STScI, CC BY How can a Big Bang have been the start of the universe, since intense ...

But there are several important anomalies, including a widely debated one called the Hubble tension. It is named after Edwin ...

Our universe may have been born in a gravitational crunch that formed a very massive black hole—followed by a bounce inside it. The Big Bang is often described as the explosive birth of the universe—a ...

Astronomers discovered an extremely hot galaxy cluster in the region that was far hotter and older than current theories ...

Imagine hearing a sound that began its journey before our galaxy even existed. That is what astronomers are doing now. They ...

Nowadays, the dark of night is interspersed with the light of stars. But before the stars were born, did light shine at the beginning of the universe? The short answer is "no." But the long answer ...