We have known for some time that the universe is expanding, and that its expansion is accelerating. But how do we know that? We’ll show you how Edwin Hubble revealed that the universe is getting ...

Most scientists think that everything that we know and experience began with the Big Bang, 14 billion years ago. But how can ...

Once we discovered that the Universe was expanding, the next scientific step was to determine what the rate of expansion was. Despite the fact that it's been more than 80 years, we still don't ...

We know the universe is and always was expanding, but we’ve never really known just how fast it’s happening. That is, until now. Researchers have used gravitational lensing to and watched a ...

The big bang kicked off the expansion of the universe The universe is constantly expanding, and that expansion is accelerating, but we aren't sure exactly how quickly. Two sets of measurements to ...

How do we know the universe is expanding? Why can’t there be an alternative explanation, say that all atoms are shrinking? Richard Swifte, Darmstadt, Germany We can’t be sure that the universe ...

The science of the universe is called cosmology — and something seems quite broken with ours. It started 100 years ago when Edwin Hubble discovered the universe is expanding.

No one knows exactly how big the whole Universe is. We can’t see it all from here on Earth, even with the best telescopes, but we can estimate the size of the observable Universe, a good (albeit ...