Nature: The constant that defines the gravitational effect between two objects, G, has one of the least precise values of all the fundamental constants. Known to just three significant figures, G was first defined more than 300 years ago by Isaac Newton. Now, research groups that have been working separately to measure G are beginning to work together. For the next two days at a conference at NIST in Gaithersburg, Maryland, researchers will be planning how to best measure G. The goal is to select a set of experiments that will be performed by multiple groups using similar equipment. Oversight will be provided by an independent team. One aspect that may be difficult in these financially pressed times is finding funding for the experiments.
