Detection Methods Detection Astrophysical Phenomena Black Holes Space-Time Binary Systems LISA Mission Supermassive Black Holes Research Methods Dark Matter Observatories Cosmic Phenomena Gravitational Wave Background Low-frequency Gravitational Waves Origins Theoretical Foundations Confirmation of Einstein's Theory Research Collaboration Frequency Range Low-Frequency Gravitational Waves Ultra-low Frequency Gravitational Waves Types Sources Research Accretion Disks Observational Astronomy Observational Techniques Black Hole Mergers LISA LISA Spacecraft LISA Observatory Black Hole Dynamics Space-Time Distortions Ultralow Frequency Gravitational Waves Cosmic History Neutron Stars Frequency Analysis Formation