How is the total mass of the universe calculated? Bob GiddingsGreen Bay, Wisconsin Calculating the total mass of the universe ...

The universe exists because matter and antimatter are not good friends. Is there a scientific reason why the universe exists?

For scientists, that has long posed a problem: According to physicists’ best current theories, matter and its counterpart, ...

If you think a galaxy is big, compare it to the size of the universe: it's just a tiny dot which, together with a huge number ...

Let me first tell you how mysterious dark energy is. Einstein added a cosmological constant to his equations to keep the ...

"It's an elegant answer, really, because we thought it was a tiny galaxy full of many separate cold stars, but it's actually, ...

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 ...

For scientists, learning more about how black holes behave is essential to understanding how the universe works. A recent ...

Scientists ultimately settled on a feeding black hole at the heart of a far-distant galaxy as the most likely engine for 3C ...

Astronomers using the Webb Telescope may have found a new type of object: cold, glowing black hole stars from the early ...

Long before galaxies sparkled in the sky or stars took shape, invisible forces stirred in the early Universe. One of those ...