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.

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 ...

13.8 billion years ago, the Big Bang occurred. The Universe was filled with matter, antimatter, radiation, and existed in an ultra-hot, ultra-dense, but expanding-and-cooling state. By today, the ...

The Big Bang occurred 13.8 billion years ago, giving rise to our Universe. But how do we know that number for its age, and might it be different?

How can the universe be 95 billion light years across when it has only been in existence for approx 14.3 billion years? If nothing can travel faster than the speed of light shouldn't the universe ...

How big is the universe? Could it be infinitely large? If the universe has an edge, what is beyond the edge? And if the universe had a beginning, what was going on before that? Our experience of ...

From the largest galaxy ever discovered to the most massive black holes in existence, this video will take you on a journey through the biggest and most awe-inspiring objects in the universe. Have you ...

Matter-antimatter asymmetry puzzles physicists. Learn how the Deep Underground Neutrino Experiment (DUNE) may find answers.

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 ...