LISA is an ESA-led gravitational-wave observatory mission including contributions from NASA, selected to address ESA’s Cosmic Vision theme, "The Gravitational Universe."
LISA will consist of three spacecraft in a triangular formation orbiting the Sun, separated from each other by 2.5 million kilometers and trailing the Earth by approximately 60 million kilometers as we orbit the Sun. These three spacecraft continuously exchange laser beams between one other to monitor for distortions in space-time caused by passing gravitational wave signals.
A space-based observatory can detect gravitational waves with frequencies from 1 mHz to 1 Hz, far below the frequencies of waves now observed from Earth-based interferometers like LIGO and Virgo. Many types of sources are expected in this frequency band including: merging black holes millions of times more massive than the Sun, smaller compact bodies (including regular stars, neutron stars, and stellar black holes), early in their binary orbits, and extreme-mass-ratio inspirals (EMRIs)—small bodies inspiraling into massive black holes.
Status/Timeline
2017 LISA Mission Selected as Large-Class Mission in ESA’s Cosmic Visions Programme
2024 LISA ‘Adopted’ by ESA, mission design complete, roles and responsibilities for all partners established.
2034 LISA expected to launch
Home pages
NASA Mission Study: https://lisa.nasa.gov/
ESA Mission Page: https://sci.esa.int/web/lisa/
LISA Consortium Page: https://www.elisascience.org/