Detection Methods Detection Astrophysical Phenomena Black Holes Space-Time Supermassive Black Holes Research Methods Binary Systems LISA Mission Dark Matter Observatories Astrophysics 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 Mass Transfer Cosmic Events 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 High-Frequency Gravitational Waves LIGO Detectors Research Techniques LIGO Statistical Techniques Merging Black Holes Wave Spectrum