In 2018, the world finalized the international system of units – also known as the metric system. But in doing so, scientists took on a new set of challenges to

In 2018, the world finalized the international system of units – also known as the metric system. But in doing so, scientists took on a new set of challenges to turn abstract unit definitions into a practical reality. Learn more in our blog post: [↧](https://t.co/nsvoDE…