The cosmos has been expanding since the Big Bang, but how fast? The answer could reveal whether everything we thought we knew about physics is wrong.

The universe is a big place, but do we really know how big? Scientists think they do, and use an array of methods to figure it out. Here are our CliffNotes.

Everything on Earth, in our solar system, our galaxy, and beyond is contained within the universe. So how much does science tell us about the all-encompassing, four-dimensional cradle that holds ...

The universe is vast, beyond what we can truly comprehend. But how big is it, really? In this video, we explore the incredible size of the universe, from its observable limits to the theories that ...

The limit of our vision extends more than 46 billion light years in all directions. But how big was the Universe when it was first born?

The term ‘Big Bang’ might make you think of a massive explosion. Put the thought out of your head. Rather than an explosion, it was the start of everything in the universe.

A big Hubble constant also means a young universe: if the cosmos is expanding quickly, it has gotten to its present size quickly, and the Big Bang is relatively recent. A Hubble constant of 100 ...

Elon Musk tweeted “the universe is a really, really big” along with this mind-blowing Ultra-HD video. It shows the camera zooming and panning over the stunning 69,536 x 22,230, 1.5 billion ...

Researchers use various proxies to measure the temperature of the cosmos, including the gas that is thought to make up most of the matter in the universe.

It's been 13.8 billion years since the Big Bang, and the Universe has been expanding the whole time. So how big was it at the moment of its birth?