The most common element in the Universe, vital for forming new stars, is hydrogen. But there’s a finite amount of it; what if we run out?

The Universe is 13.8 billion years old, going back to the hot Big Bang. But was that truly the beginning, and is that truly its age?

Practically all of the matter we see and interact with is made of atoms, which are mostly empty space. Then why is reality so… solid?

Holograms preserve all of an object’s 3D information, but on a 2D surface. Could the holographic Universe idea lead us to higher dimensions?

In the 20th century, many options abounded as to our cosmic origins. Today, only the Big Bang survives, thanks to this critical evidence.

No matter how good our measurement devices get, certain quantum properties always possess an inherent uncertainty. Can we figure out why?

At a fundamental level, only a few particles and forces govern all of reality. How do their combinations create human consciousness?

In all the Universe, only a few particles are eternally stable. The photon, the quantum of light, has an infinite lifetime. Or does it?

Our Universe requires dark matter in order to make sense of things, astrophysically. Could massive photons do the trick?

For some reason, when we talk about the age of stars, galaxies, and the Universe, we use “years” to measure time. Can we do better?

If you think of the Big Bang as an explosion, we can trace it back to a single point-of-origin. But what if it happened everywhere at once?

Is the Universe finite or infinite? Does it go on forever or loop back on itself? Here’s what would happen if you traveled forever.

Life arose on Earth very early on. After a few billion years, here we are: intelligent and technologically advanced. Where’s everyone else?

Many contrarians dispute that cosmic inflation occurred. The evidence says otherwise.

The history of life on Earth took many meandering turns before it gave rise to us. When Earth first formed, all the raw ingredients for life — atoms, molecules, a potentially habitable planet […]

We’re a long way from the beginnings of life on Earth. Here’s the key to how we got there. The Universe was already two-thirds of its present age by the time […]

A climate catastrophe 2 billion years ago almost ended life on Earth. Here’s the biggest lesson of all. Although it was more than 4½ billion years ago that planet Earth formed, […]

One moment, every particle in the Universe was massless. Then, they weren’t anymore. Here’s how it happened. In the earliest stages of the hot Big Bang, the Universe was filled […]

Saw “Solar System Questions” by xkcd? Here’s what science thinks it knows. “Put two ships in the open sea, without wind or tide, and, at last, they will come together. […]