In this video, we explore the vastness of the universe and attempt to quantify its size. We delve into the concepts of cosmic ...

Galaxies, like so many other astronomical objects, are surprisingly difficult to define. Here’s a hand-wavy attempt: a galaxy is a collection of stars, gas, dust and dark matter all held together by ...

The surface of Earth is finite. We can measure it. If it was expanding, then its size would grow with time. And once again, good ol' Earth helps us understand what the universe might be doing beyond ...

The question of whether the cosmos goes on forever is no longer just a late night thought experiment, it is a live research problem that cuts to the heart of modern physics. Astrophysicists are using ...