GW240925 & GW250207

On 12 May 2026, the LIGO-Virgo-KAGRA Collaboration announced the discovery of two binary black hole systems observed during the fourth observing run: GW240925 and GW250207. Both systems had very high signal-to-noise ratios of 32 and 69, respectively. This allowed the first informative application of a technique called astrophysical calibration.

Infographic: properties of GW240925 and GW250207. [Credit: S. Galaudage / Northwestern U./ Adler Planetarium / LVK Collaboration.]
Infographic: properties of GW240925 and GW250207. [Credit: S. Galaudage / Northwestern U./ Adler Planetarium / LVK Collaboration.]

Publications & Documentation

Infographic: detector calibration.[Credit: S. Galaudage / Northwestern U./ Adler Planetarium / LVK Collaboration.]
Infographic: detector calibration.[Credit: S. Galaudage / Northwestern U./ Adler Planetarium / LVK Collaboration.]
Infographic: analogy between astrophysical calibration music auto-tuning. [Credit: S. Galaudage / Northwestern U./ Adler Planetarium / LVK Collaboration.]
Infographic: analogy between astrophysical calibration and music auto-tuning. [Credit: S. Galaudage / Northwestern U./ Adler Planetarium / LVK Collaboration.]
Infographic: improving sky localization via astrophysical calibration. [Credit: S. Galaudage (Northwestern U. & Adler Planetarium) / S. Biscoveanu / LVK Collaboration.]
Infographic: improving sky localization via astrophysical calibration. [Credit: S. Galaudage (Northwestern U. & Adler Planetarium) / S. Biscoveanu / LVK Collaboration.]

Additional Images/Media

Artistic impression of astrophysical calibration. [Credit: C. Knox, OzGrav/Swinburne]
Artistic impression of astrophysical calibration. [Credit: C. Knox, OzGrav/Swinburne]
Animation and sonification of calibrated (left) and miscalibrated (right) waveforms for GW240925. The miscalibration effect is exaggerated by a factor of 1000. [Credit: E. Todd, U. of Glasgow]