The other day, I did something I am dispatched to do every now and then: bought a kilo of basmati rice. It came nicely packaged in a sealed bag. It feels about what I think a kilogram should feel like ...

The NIST-4 Kibble balance, an electromagnetic weighing machine that is used to measure Planck's constant, and in turn, redefine the kilogram. Jennifer Lauren Lee / NIST Locked in a vault that requires ...

When news breaks, you need to understand what actually matters — and what to do about it. At Vox, our mission to help you make sense of the world has never been more vital. But we can’t do it on our ...