Automated analyses did not initially identify this event as information about the state of the Hanford detector was not being correctly recorded.

[1] The event was found by a researcher at the Max Planck Institute for Gravitational Physics by visual inspection of triggers from the Livingston detector.

Analysis indicated the signal resulted from the inspiral and merger of a pair of black holes (BBH) with 31.2+8.4−6.0 and 19.4+5.3−5.9 times the mass of the Sun, at a distance of 880+450−390 megaparsecs (2.9+1.5−1.3 billion light years) from Earth.

The peak luminosity of GW170104 was 3.1+0.7−1.3×1049 W.[1] The spin axes of the black holes were likely misaligned with the axis of the binary orbit.

The competing scenario, that the system was formed out of a binary star system consisting of two normal (main sequence) stars, is not ruled out but is disfavored as black holes formed in such a binary are more likely to have positively aligned spins.