Zak and Derek discuss the "controversial" value of Newton's gravitational constant G. They cover the history of its measurement and how the value (and confidence in that value) has changed over time. Gravitational G wiki page: https://en.wikipedia.org/wiki/Gravitational_constant Relative uncertainty of phsyical constants: https://codata.org/blog/2015/08/04/codata-recommended-values-of-the-fundamental-physical-constants-2014/ Different G experiments with uncertainty bars: https://www.researchgate.net/publication/344933668/figure/fig2/AS:1019607263477760@1620104723443/The-eleven-values-of-G-adopted-in-CODATA-2014-after-2000-and-our-latest-two-values.png