3D velocity analysis of wide binaries supports modified gravity at low acceleration

Wide binary stars with separation greater than about 2000 astronomical units are interesting natural laboratories that allow a direct probe of gravity at low acceleration weaker than about 1 nanometer per second squared. Astrophysicist Kyu-Hyun Chae at Sejong University (Seoul, South Korea) has developed a new method of measuring gravity with all three components of the velocities (3D velocities) of stars, as a major improvement over existing statistical methods relying on sky-projected 2D veloc...