A 2018 study using the Navy Precision Optical Interferometer measured the angular diameter as . The mass includes a retroreflector and terminates one arm of a Michelson interferometer. Currently, the most sensitive is LIGO the Laser Interferometer Gravitational Wave Observatory. Spinning or accelerating an interferometer creates a gravitational effect. Atomic populations show interference in a Ramsey interferometer. The LIGO Livingston Observatory houses one laser interferometer in the primary configuration. A is the relevant type of coherence for the Young's double-slit interferometer. The Michelson stellar interferometer is used for measuring the diameter of stars. Its main array will have 50 antennas acting as a single interferometer. Michelson designed an instrument called the Michelson interferometer to accomplish this. Virgo is a Michelson interferometer whose mirrors are suspended. E-modes were first seen in 2002 by the Degree Angular Scale Interferometer (DASI). This principle is the basis for a Michelson interferometer. Another highly sensitive interferometer (KAGRA) is currently in the design phase. This arrangement is also called a Sagnac interferometer.