The atmosphere, a thin veil of molecules enveloping Earth, reaches about 20 miles (32 kilometers) above the planet's surface.

That bleak future may never arrive, however, if the expansion slows. In fact, in one scenario, the universe could even re-collapse. There’s a name for that: the “Big Crunch.” Astronomers ...

Well, it's something called the "Hubble tension," and it's a dispute between observational astronomers and theoretical cosmologists about who's been wrong about how fast the universe is expanding.

The rate at which the universe is expanding has implications for its ultimate fate: heat death, a Big Rip, eventual collapse into a new all-encompassing singularity, or something else altogether.

The expansion of the universe is, in some ways, similar. But this analogy gets one thing wrong – while the dough expands into the baking pan, the universe doesn’t have anything to expand into.

That’s an observation, made around a decade ago, that the universe seems to be expanding faster than it should be according to cosmologists’ understanding of its earliest days. Now, two years of James ...

What is the universe expanding into if it’s already infinite? – Mael, age 10, Missoula, Montana When you bake a loaf of bread or a batch of muffins, you put the dough into a pan. As the dough ...