LISA is an international proposed project headed by the European Space Agency with the aim of detecting more massive black hole and neutron star merger. The LISA with its three spacecraft separated by millions of mile (that's larger than Earth) relays lasers back and forth to detect distortion in space—gravitational waves. LISA is an upgrade to the current Earth-based detector LIGO (Light Interferometer Gravitational Wave Observatory) at Hanford in eastern Washington and all the way to another detector near Livingston, Louisiana.
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