Our fourth observing run (O4) has seen our detectors perform better than ever before. Together with Virgo and KAGRA we have identified more gravitational-wave candidates than in all previous observing runs combined
Our Rapid Response Teams celebrate the end of our fourth observing run. Well done everyone!
https://www.ligo.caltech.edu/news/ligo20251118
O4 was a success thanks to lots of hard work from across the world.
The final #GravitationalWave candidate of O4? #S251117dq
If real, the source is probably a binary black hole (chirp mass ~22–44 solar masses)
False alarm rate 1 in 5.4×10^6 yr
GraceDB https://gracedb.ligo.org/superevents/S251117dq/
GCN https://gcn.nasa.gov/circulars/42727
Rating 🦉🥐🏔️
Last night's #GravitationalWave candidate #S251116en
If real, the source is probably a binary black hole (chirp mass ~22–44 solar masses)
False alarm rate 1 in 24,000 yr
GraceDB https://gracedb.ligo.org/superevents/S251116en
GCN https://gcn.nasa.gov/circulars/42708
Rating 🦆🦆🎀
Latest false alarm rate for #S251112cm with an updated background model of about 1 in 4 yr, so slightly less significant
GCN https://gcn.nasa.gov/circulars/42690
Rating 📏☕
Oo! Interesting #GravitationalWave candidate #S251112cm potentially from a *subsolar* mass source
If real, the source probably has chirp mass ~0.1–0.87 solar masses
False alarm rate 1 in 6.2 yr
GraceDB https://gracedb.ligo.org/superevents/S251112cm/
GCN https://gcn.nasa.gov/circulars/42650
Rating 📏🍬
An evening stroll #GravitationalWave candidate #S251108fi
If real, the source is probably a binary black hole (chirp mass ~11–44 solar masses)
False alarm rate 1 in 24000 yr
GraceDB https://gracedb.ligo.org/superevents/S251108fi/
GCN https://gcn.nasa.gov/circulars/42624
Rating 🦢🎼⛄
#GravitationalWave candidate #S251108dn
If real, the source is probably a binary black hole (chirp mass ~5.5–11 solar masses). A glitch in Livingston may impact analysis
False alarm rate 1 in 3.3 10^9 yr
GraceDB https://gracedb.ligo.org/superevents/S251108dn
GCN https://gcn.nasa.gov/circulars/42619
Rating 🧙🚧🍕
Celebrate Wednesday with #GravitationalWave candidate #S251105aj
If real, the source is probably a binary black hole (chirp mass ~22–44 solar masses)
False alarm rate 1 in 39000 yr
GraceDB https://gracedb.ligo.org/superevents/S251105aj/
GCN https://gcn.nasa.gov/circulars/42587
Rating 🟦🍰🦢
Our #GW241011 and #GW241110 discovery paper is now on the arXiv
https://arxiv.org/abs/2510.26931
If you would like to catch up on the highlights, checkout out our Science Summary
LIGO
Dr Christopher Berry