QRM issues on LISA experiment

LISA (Laser Interferometer Space Antenna) is a joint NASA-ESA mission for fundamental physics studies, which aims at directly detecting gravitational waves. Gravitational waves are expected to cause a space-time distortion, which acts on a plane perpendicular to the wave's direction and has two orthogonal components with equal modulus and opposite sign. LISA will detect such gravitational strains by means of three Michelson laser interferometers measuring variations in the relative position of three satellites forming an equilateral triangle formation and flying in heliocentric orbit. To ensure detection of gravitational waves, the interferometer end mirrors have to be shielded against any non-gravitational force, especially those acting in the same frequency range as the gravitational waves. While the performance requested to the interferometer, though high, is not exceptional, the quality and the reliability of the shielding effect require careful investigation. The present paper will illustrate the big picture of the LISA project, focusing on the most relevant issues from the QRM point of view.