WAIT, I THOUGHT THE SCIENCE WAS SETTLED: Forget what you’ve learned – scientists just created a stable helium compound. “If you remember your high school chemistry, you’ll know that helium is a bit of an oddball. This noble gas is the least reactive element on the periodic table, and thanks to its full outer shell, conventional wisdom states that helium cannot interact with other atoms to create stable compounds. While other noble gas elements have shown signs of forming compounds under extreme pressure, helium has remained firmly exclusive – until now. Scientists report creating what appears to be a stable helium-sodium compound, and it challenges some of the most basic assumptions of modern chemistry.”