SPACE | Studying gravitational waves from the Moon

GSSI, INAF, INFN, INGV, and the University of Camerino have signed a collaboration agreement for the development of a detector on the lunar surface. The program will be funded by the Italian Space Agency.

A national consortium, led by the Gran Sasso Science Institute (GSSI), which includes the University of Camerino, the National Institute for Astrophysics (INAF), the National Institute of Geophysics and Volcanology (INGV), and the National Institute for Nuclear Physics (INFN), will conduct preparatory studies for the Lunar Gravitational-wave Antenna (LGWA). The scientific collaboration agreement, signed by the institutions on January 21, marks a fundamental step forward for this ambitious project aimed at searching for gravitational waves from the Moon. LGWA was selected in 2023 by the European Space Agency (ESA) in Reserve Pool of Science Activities for the Moon, receiving the highest rating among all the proposed projects. Following this success, the Italian Space Agency (ASI) has chosen to fund the preparatory studies for the projects selected by ESA with Italian leadership.

Funded activities currently focus on the technological development of the lunar payload (GSSI, University of Camerino, INFN, and INAF), followed by specific activity packages related to lunar soil characterization studies with the production of a synthetic seismic wave propagation model (INGV) and gravitational wave science (INAF). Current funding will support the first two years of preparatory studies, with the possibility of extending the activities beyond 2027.

The idea of ​​making the Moon itself part of a gravitational detector by exploiting its intrinsic response to gravitational waves was the basis of the work of American physicist Joseph Weber in the 1970s. The American scientist contributed to the construction of the Lunar Surface Gravimeter, a gravimeter installed on the lunar surface in 1972 during the Apollo 17 mission. The goal was to observe lunar vibrations caused by gravitational waves, but a design flaw in the meter made it impossible to continue the experiment.

Over fifty years later, LGWA's construction of a lunar gravitational wave antenna could mark a turning point and open up new horizons for astrophysics and beyond. The instrument would be capable of detecting signals from compact binary systems consisting of galactic white dwarfs to massive black holes at cosmic distances, or even gathering data on the internal structure of our natural satellite and shedding light on the mechanisms of its earthquakes.