"New telescopes join LIGO in search for gravitational waves"

The LIGO-Virgo-KAGRA (LVK) Collaboration has begun Observation Run 4 (O4), the latest effort to detect gravitational waves with newly upgraded detectors. The collaboration combines four detectors on three continents: LIGO's two detectors, Virgo in Europe, and KAGRA in Japan. With upgraded sensitivity, the detectors can pick out weaker or more distant gravitational waves, allowing scientists to pick up more events and answer questions about where black holes tend to form. LVK's current schedule calls for O4 to run for 18 months, into 2025.