WTests of general relativity
WApache Point Observatory Lunar Laser-ranging Operation
WBinary pulsar
WFrame-dragging
WGravitoelectromagnetism
WGravity Probe A
WGravity Probe B
WHafele–Keating experiment
WHughes–Drever experiment
WLunar Laser Ranging experiment
WPound–Rebka experiment
WSolar eclipse of May 29, 1919
WVulcan (hypothetical planet)