Most wavelengths of light could penetrate this neutral medium, but there was very little in the way of light sources to produce it. But from this hydrogen and helium, the first stars were born. Those ...

So, you’re driving a car at half the speed of light. (Both hands on the wheel, please.) You turn on the headlights. How fast would you see this light traveling? What about a person standing by the ...

A time crystal is a form of matter that shows continuous, repeating patterns over time, much like how atoms in a normal crystal repeat in space. Examples once existed in only complex, quantum matter, ...

Researchers in Germany have unveiled the Metafiber, a breakthrough device that allows ultra-precise, rapid, and compact control of light focus directly within an optical fiber. Unlike traditional ...

Interstellar object 3I/ATLAS — which is zooming through our inner solar system — appears to be emitting its own light, according to Harvard astrophysicist Avi Loeb. The observation by Loeb, if ...