3 Smart Things About Helium

摘要

1 Although helium is the second-most-plentiful element in the cosmos-ifs synthesized in stars by nuclear fusion-Earth is running short of the noble gas. Extracted from natural gas, our supply accumulated in the planet's crust over billions of years-the result of radioactive decay. One-third of that stash lies in the Texas panhandle, and if it continues to be consumed at the current rate, it'll be gone in nine years.