The observable universe is vast, extending about 93 billion light-years across, containing galaxies, stars, planets, and all of the observable phenomena that make up our cosmic home. But what exists ...

The creation of the universe has long puzzled scientists: how could it begin if time itself didn’t exist? The Big Bang marks ...

However, the observable universe extends farther than 13.8 billion light-years in every direction because, for all the time space has existed, it’s also been expanding.

Physicists are rethinking time itself. Long treated as a basic part of the universe, time may instead be an illusion—a side ...

Discover why the universe has no centre or edge. Learn how the Big Bang happened everywhere at once and why every observer ...

How old is the universe? Learn more about the age of the Universe, from it's explosive beginnings to how we on Earth can ...

Astronomers may have found the long-missing half of the universe's regular matter—and it appears to have been right under our noses all this time. Models of how the universe has evolved since ...

The spins of some early galaxies could be a clue that the entire observable universe exists within a black hole—except, that is, for all the evidence to the contrary ...

New observations with the Atacama Cosmology Telescope in Chile reveal the earliest-ever "baby pictures" of our universe, showing some of the oldest light we can possibly see.

In this framework, our entire observable universe lies inside the interior of a black hole formed in some larger “parent” universe. We are not special, no more than Earth was in the geocentric ...

There are so many stars in the universe—hundreds of billions of them in our galaxy alone, which is, in turn, one of some 125 billion galaxies in the observable universe—that it would be ...