Why is Gravity's strength so hard to measure? NIST has a new clue

Physicist Michael Schlamminger at NIST spent a decade measuring gravity's fundamental constant, known as big G, using a torsion balance with metal cylinders and sapphire masses. His result was 0.0235% lower than a French experiment. Despite centuries of effort since Henry Cavendish's 1798 experiment, big G remains the least precisely known of the four fundamental forces.

Every measurement is important, because the truth matters. For me, making an accurate measurement is a way of bringing order to the universe, whether or not the number agrees with the expected value.