Scientists opened a sealed envelope after 10 years. Gravity still didn’t make sense

Filed by Dr. Kai Vega

A decade-long NIST experiment has produced a new measurement of the universal gravitational constant that differs unexpectedly from another leading result, deepening a 225-year-old physics puzzle. The discrepancy is tiny, but for one of nature’s most fundamental constants, it is large enough to keep scientists wondering whether hidden experimental errors or something more surprising is involved.