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Natural Sciences Active Updated Jul 13, 2026

Black holes built from earlier black hole mergers

Eleven years after LIGO's first detection of two black holes merging, the gravitational-wave catalog has grown to 390 confirmed events, some too heavy for a single dying star to have produced on its own. The leading explanation is that these are second-generation black holes, formed when black holes that already merged once merge again. The arc will run as astronomers try to work out how common these repeat mergers are and where the first-generation black holes that produce them come from.

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  1. Jul 13, 2026 Latest

    As of June 2026, LIGO's gravitational-wave catalog stood at 390 confirmed detections since its first-ever direct detection in 2015 of two black holes of about 36 and 29 solar masses merging. Some of the newly found black holes are heavier than a single collapsing star should produce, leading astronomers to conclude they are second-generation objects built from an earlier black hole merger.

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